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                                                                   Exhibit 10.10



                                SECOND AMENDMENT

                                       TO

                   FIFTH AMENDED AND RESTATED CREDIT AGREEMENT

         THIS SECOND AMENDMENT TO FIFTH AMENDED AND RESTATED CREDIT AGREEMENT is
dated as of December 6, 1999 (this "Second Amendment"), and entered into among
PINNACLE TOWERS INC., a Delaware corporation (the "Borrower"), the Lenders
signatory hereto, BANK OF AMERICA, N.A., a national banking association,
individually and as Administrative Agent (in such latter capacity, the
"Administrative Agent").

                                   WITNESSETH:

         WHEREAS, the Borrower, the Administrative Agent, and Lenders entered
into a Fifth Amended and Restated Credit Agreement, dated as of September 17,
1999, as amended by that certain First Amendment to Fifth Amended and Restated
Credit Agreement, dated as of October 29, 1999 (as amended and as further
amended, restated, or otherwise modified from time to time, the "Credit
Agreement"). Unless specifically defined or redefined below, capitalized terms
used herein shall have the meanings ascribed thereto in the Credit Agreement;

         WHEREAS, the Lenders, the Borrower, and the Administrative Agent have
agreed to amend the Credit Agreement to make certain changes to the terms
therein upon the terms and conditions set forth below;

         NOW, THEREFORE, for valuable consideration hereby acknowledged, the
Borrower, the Lenders, and the Administrative Agent agree as follows:

         SECTION 1. Amendment to Second Paragraph of the BACKGROUND Section. The
second full paragraph of the BACKGROUND section of the Credit Agreement on page
1 of the Credit Agreement shall be deleted in its entirety and the following
paragraph substituted in its stead:

                  WHEREAS, Borrower and Administrative Agent have agreed to
         restructure, extend, renew, refinance, and restate such indebtedness
         under the Original Credit Agreement as set forth herein to provide for
         three separate facilities 1) a seven year reducing revolver facility in
         the initial amount of $235,000,000 (with (i) a subfacility provided by
         Bank of America Canada to a Canadian subsidiary of the Borrower in a
         maximum amount not to exceed $16,464,800 Canadian Dollars, such amount
         approximately equal to $11,000,000 on the closing date and (ii) a
         swingline subfacility in the maximum amount of $5,000,000 provided by
         Bank of America, N.A.), (such reducing revolver facility has an
         uncommitted increase option which could increase the reducing revolver
         facility to $435,000,000), 2) a seven year delayed draw acquisition
         term loan in the amount of $125,000,000, and 3) an eight year term loan
         in the amount of $110,000,000 (which must be fully drawn on the date of
         closing), and to make certain other agreed to changes to the existing
         credit facility among the parties thereto. Of the proceeds of the
         facility referenced in 1) above, $219,957,000
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         be applied on the date hereof to refinance indebtedness under the
         Original Credit Agreement Term Loan A (as defined in the Original
         Credit Agreement) and such portions of Revolver A and Revolver B (as
         each is defined in the Original Credit Agreement) that constitute
         Acquisition Debt (as defined below).

         SECTION 2.  Amendment to Article I Definitions.

         (a) The definition of "Advances" in Article I of the Credit Agreement
shall be deleted in its entirety and the following definition of "Advances"
shall be substituted in its stead:

                  "Advance" means an advance made by a Lender to the Borrower
         pursuant to Section 2.01 hereof which may be a Revolver Advance, a Term
         Loan A Advance or a Term Loan B Advance (and may either be Base Advance
         or a LIBOR Advance), and which such Advance may also be a Refinancing
         Advance or a Swingline Advance.

         (b) The definition of "Commitment" in Article I of the Credit Agreement
shall be deleted in its entirety and the following definition of "Commitment"
shall be substituted in its stead:

                  "Commitment" means $235,000,000 (as such amount has been or
         may be increased prior to June 30, 2001 in accordance with the terms of
         Section 2.18 hereof) minus the sum of (a) the undrawn face amount of
         all Letters of Credit, plus (b) the sum of all reimbursement
         obligations under Article III hereof, plus (c) the Canada Indebtedness
         Amount, plus (d) all outstanding Swingline Advances, in each case as
         such Commitment may be further reduced from time to time, or
         terminated, pursuant to Sections 2.06, 2.11 or 9.02 hereof.

         (c) The definition of "Note" in Article I of the Credit Agreement shall
be deleted in its entirety and the following definition of "Note" shall be
substituted in its stead:

                  "Note" means each Note of the Borrower evidencing Advances
         hereunder, substantially in the forms of Exhibits A-1, A-2, A-3 and A-4
         hereto, together with any extension, renewal or amendment thereof, or
         substitution therefor.

         (d) The definitions of "Swingline Advance", "Swingline Bank",
"Swingline Commitment", "Swingline Facility", "Swingline Loan", "Swingline Note"
and "Swingline Rate" shall be added to Article I in alphabetical order and shall
read in their entirety as follows:

                  "Swingline Advance" means an Advance made pursuant to Section
         2.01(a)(ii) hereof.

                  "Swingline Bank" means Bank of America, N.A. and any
         Administrative Agent successor thereto appointed in accordance with
         Section 10.06 hereof.

                  "Swingline Commitment" means the lesser of (a) $5,000,000 and
         (b) the remainder of the Commitment minus the sum of all outstanding
         Revolver Advances.


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                  "Swingline Facility" means that certain swingline facility
         available to the Borrower in accordance with the terms of Section
         2.01(a)(ii) hereof.

                  "Swingline Loan" means the loans made under the Swingline
         Facility from time to time.

                  "Swingline Note" means the Swingline Note of the Borrower
         payable to the order of the Swingline Bank, evidencing Swingline
         Advances hereunder, substantially in the form of Exhibit A-4 hereto,
         together with any extension, renewal or amendment thereof or
         substitution therefor.

                  "Swingline Rate" means an interest rate per annum equal to the
         Base Rate minus .50%, provided that the Swingline Rate shall never be
         less than zero.

         SECTION 3. Amendment of Section 2.01(a). Section 2.01(a) of the Credit
Agreement shall be deleted in its entirety and the following Section 2.01(a)
shall be substituted in its stead:

                  (a) The Revolver Loan.

                  (i) Revolver Advances. Each Lender severally agrees, on the
         terms and subject to the conditions hereinafter set forth, to make
         Advances to the Borrower on a Business Day during the period from the
         Closing Date to the First Maturity Date, in an aggregate principal
         amount not to exceed at any time outstanding such Lender's Revolver
         Specified Percentage of the Commitment. Subject to the terms and
         conditions of this Agreement, the Borrower may borrow, repay and
         reborrow the Revolver Advances; provided, however, that at no time
         shall the sum of all outstanding Revolver Advances exceed the
         Commitment.

                  (ii) Swingline Advances. The Borrower may request the
         Swingline Bank to make, and the Swingline Bank shall make, on the terms
         and conditions hereinafter set forth, Advances to the Borrower from
         time to time on any Business Day during the period from the Closing
         Date to the First Maturity Date in an aggregate principal amount not to
         exceed at any time the Swingline Commitment. Each Swingline Advance
         shall be in an amount not less than $50,000 and shall bear interest at
         the Swingline Rate. Within the limits of the Swingline Facility and
         subject to the terms hereof, Swingline Advances may be repaid and then
         reborrowed; provided, that each Swingline Advance must be repaid (which
         such repayment, subject to the terms of this Agreement, may be made
         with the proceeds of Revolver Advances) no later than 30 calendar days
         after the date such Swingline Advance was made.

         SECTION 4. Amendment of Section 2.02. Section 2.02 of the Credit
Agreement shall be deleted in its entirety and the following Section 2.02 shall
be substituted in its stead:

         2.02. Making Advances.

                  (a) Each Borrowing of Advances shall be made upon the written
         notice of the Borrower, received by Administrative Agent not later than
         (i) 10:00 a.m. three


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         Business Days prior to the date of the proposed Borrowing, in the case
         of LIBOR Advances and (ii) 10:00 a.m. on the date of such Borrowing, in
         the case of Base Advances. Each such notice of a Borrowing (a
         "Borrowing Notice") shall be by telecopy or telephone, promptly
         confirmed by letter, in substantially the form of Exhibit D hereto
         specifying therein:

                           (i) the date of such proposed Borrowing, which shall
                  be a Business Day;

                           (ii) the Type of Advances of which the Borrowing is
                  to be comprised, and whether such Borrowing is a Revolver
                  Advance, a Swingline Advance, a Term Loan A Advance or a Term
                  Loan B Advance (provided that, other than with respect to the
                  Term Loan A Initial Advance and the Term Loan B Initial
                  Advance, all such borrowings under the Term Loan A and the
                  Term Loan B shall be Refinancing Advances);

                           (iii) the amount of such proposed Borrowing which,
                  (A) in the case of Advances under the Revolver Loan, shall not
                  exceed the unused portion of the Commitment, in the case of
                  Advances under the Swingline Loan, shall not exceed the unused
                  portion of the Swingline Commitment, in the case of the Term
                  Loan A Initial Advance, shall not exceed the Term Loan A
                  amount of $125,000,000, and in the case of the Term Loan B
                  Initial Advance, shall not exceed the Term Loan B amount of
                  $110,000,000, (B) shall, in the case of a Borrowing of Base
                  Advances other than Swingline Advances, be in an amount of not
                  less than $500,000 or an integral multiple of $50,000 in
                  excess thereof (or any lesser amount if such amount is the
                  remaining undrawn portion under the Commitment) and (C) shall,
                  in the case of a Borrowing of LIBOR Advances, be in an amount
                  of not less than $5,000,000 or an integral multiple of
                  $100,000 in excess thereof; and

                           (iv) if the Borrowing is to be comprised of LIBOR
                  Advances, the duration of the initial Interest Period
                  applicable to such Advances.

                  If the Borrowing Notice fails to specify the duration of the
         initial Interest Period for any Borrowing comprised of LIBOR Advances,
         such Interest Period shall be three months. Administrative Agent shall
         promptly notify Lenders of each such notice except any notice with
         respect to a Swingline Advance. Each Lender shall, before 1:00 p.m. on
         the date of each Advance hereunder (other than a Refinancing Advance or
         Swingline Advance), make available to Administrative Agent, at its
         office at Bank of America Plaza, 901 Main Street, Dallas, Texas 75202,
         such Lender's Applicable Specified Percentage of the aggregate Advances
         to be made on that day in immediately available funds.

                  (b) Unless any applicable condition specified in Article IV
         has not been satisfied, Administrative Agent will make the funds
         promptly available to the Borrower (other than with respect to a
         Refinancing Advance or a Swingline Advance)




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         by wiring such amounts pursuant to any wiring instructions specified by
         the Borrower to the Administrative Agent in writing.

                  (c) After giving effect to any Borrowing, (i) there shall not
         be more than ten different Interest Periods in effect, (ii) the
         aggregate principal amount of outstanding Revolver Advances shall not
         exceed the Commitment, and (iii) the aggregate principal amount of
         outstanding Swingline Advances shall not exceed the Swingline
         Commitment.

                  (d) No Interest Period applicable to any Revolver Advance and
         Term Loan A Advance shall extend beyond the First Maturity Date, and no
         Interest Period applicable to any Term Loan B Advance shall extend
         beyond the Final Maturity Date.

                  (e) Unless a Lender shall have notified Administrative Agent
         prior to the date of any Advance that it will not make available its
         Applicable Specified Percentage of any such Advance (that is not a
         Refinancing Advance or a Swingline Advance), the Administrative Agent
         may assume that such Lender has made the appropriate amount available
         in accordance with Section 2.02(a) hereof, and Administrative Agent
         may, in reliance upon such assumption, make available to the Borrower a
         corresponding amount. If and to the extent any Lender shall not have
         made such amount available to Administrative Agent, such Lender and the
         Borrower severally agree to repay to Administrative Agent immediately
         on demand such corresponding amount together with interest thereon,
         from the date such amount is made available to the Borrower until the
         date such amount is repaid to Administrative Agent, at (i) in the case
         of the Borrower, the Base Rate, and (ii) in the case of such Lender,
         the Federal Funds Rate.

                  (f) The failure by any Lender to make available its Applicable
         Specified Percentage of any Advance hereunder shall not relieve any
         other Lender of its obligation, if any, to make available its
         Applicable Specified Percentage of any Advance. In no event, however,
         shall any Lender be responsible for the failure of any other Lender to
         make available any portion of any Advance.

                  (g) The Borrower shall indemnify each Lender against any
         Consequential Loss incurred by each Lender as a result of (i) any
         failure to fulfill, on or before the date specified for the Advance,
         the conditions to the Advance set forth herein or (ii) the Borrower's
         requesting that an Advance not be made on the date specified in the
         Borrowing Notice.

                  (h) In the case of Swingline Advances, the Borrower shall give
         the Swingline Bank and the Administrative Agent irrevocable telephonic
         notice in accordance with Section 2.02(a) hereof on the date of any
         proposed Swingline Advance (provided, however, (i) the Borrower shall
         deliver written notice at least once a week confirming the telephonic
         notices given by the Borrower with respect to Swingline Advances during
         the immediately preceding week and (ii) that the Borrower's failure to
         confirm any telephonic notice in writing shall not invalidate any
         notice so given) of its intention to borrow or reborrow a Swingline
         Advance. Such




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         notice of borrowing shall specify (i) the requested funding date, which
         shall be a Business Day and (ii) the amount of the proposed Swingline
         Advance. The Swingline Bank shall, not later than 2:00 p.m., Dallas,
         Texas time, on the date of any Swingline Advance, deliver to the
         Administrative Agent at its address set forth herein, the amount of
         such Swingline Advance in immediately available funds in accordance
         with the Administrative Agent's instructions. Prior to 2:30 p.m.,
         Dallas, Texas time, on the date of any Swingline Advance, the
         Administrative Agent shall, subject to the conditions set forth in
         Article IV hereof, disburse the amount made available to the
         Administrative Agent by the Swingline Bank by (i) transferring such
         amounts by wire transfer pursuant to the Borrower's instruction or (ii)
         in the absence of such instructions, crediting such amounts to the
         account of the Borrower maintained with the Administrative Agent.
         Forthwith upon demand by the Swingline Bank at any time, including, but
         without limitation (A) after the occurrence of a Default or Event of
         Default, (B) after the occurrence of a Material Adverse Change, (C)
         after the date that is 30 days after the date any Swingline Advance is
         made and (D) in any event upon the making of the direction specified by
         Section 9.02 hereof to authorize the Administrative Agent to declare
         the Obligations due and payable pursuant to the provisions of Section
         9.02 hereof, each Lender, notwithstanding (i) the failure of the
         Borrower at such time to satisfy each condition specified in Article IV
         hereof or (ii) any reduction in the Commitment, shall make by 12:00
         noon (Dallas, Texas time) on the first Business Day following receipt
         by such Lender of notice from the Swingline Bank, a Revolver Advance
         which is a Base Advance in an amount equal to the product of (i) the
         Revolver Specified Percentage of such Lender times (ii) the aggregate
         outstanding principal amount of the Swingline Advances (a "Mandatory
         Borrowing"). The proceeds of such Revolver Advances shall be applied by
         the Administrative Agent to repay the outstanding Swingline Advances.
         Each Lender hereby irrevocably agrees to make a Revolver Advance
         pursuant to each Mandatory Borrowing in the amount and in the manner
         specified in the preceding sentence and on the date specified in
         writing by the Swingline Bank notwithstanding (i) that the amount of
         the Mandatory Borrowing may not comply with any minimum amount for
         Borrowings otherwise required hereunder, (ii) whether any conditions
         specified in Article IV hereof are then satisfied, (iii) whether a
         Default or an Event of Default then exists, (iv) the date of such
         Mandatory Borrowing and (v) the aggregate amount of the Commitment at
         such time.

                 If any Mandatory Borrowing cannot for any reason be made on the
         date otherwise required above (including, without limitation, as a
         result of the commencement of a proceeding under the Bankruptcy Code
         with respect to the Borrower), each Lender hereby agrees that it shall
         forthwith purchase (as of the date on which the Mandatory Borrowing
         would otherwise have occurred, but adjusted for any payments received
         from the Borrower on or after such date and prior to such purchase)
         from the Swingline Bank such participations in the outstanding
         Swingline Advances as shall be necessary to cause the Lenders to share
         in such Swingline Advances ratably based upon their Revolver Specified
         Percentages of the Commitment (determined before giving effect to any
         termination of the Commitment); provided that (i) all interest payable
         on the Swingline Advance shall be for the account




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         of the Swingline Bank until the date as of which the respective
         participation is required to be purchased and, to the extent
         attributable to the purchased participation, shall be payable to the
         participating Lender from and after such date and (ii) at the time any
         purchase of participations pursuant to this sentence is actually made,
         the purchasing Lender shall be required to pay the Swingline Bank
         interest on the principal amount of the participation purchased for
         each day from and including the day upon which the Mandatory Borrowing
         would otherwise have occurred to but excluding the date of payment for
         such participation, at the overnight Federal Funds Rate for the first
         five days and at the rate otherwise applicable to Revolver Advances
         hereunder for each day thereafter.

         SECTION 5. Addition of Section 2.03(a)(iv). A new Section 2.03(a)(iv)
shall be added to the end of Section 2.03(a) of the Credit Agreement to read in
its entirety as follows:

                  (iv) The Swingline Advances made by the Swingline Bank shall
         be evidenced by a Swingline Note in the amount of $5,000,000 (as the
         same may be modified pursuant to Section 11.04 hereof) in the form of
         Exhibit A-4 hereto.

         SECTION 6. Amendment of Section 2.04. Section 2.04 of the Credit
Agreement shall be deleted in its entirety and the following Section 2.04 shall
be substituted in its stead:

                  2.04. Optional Prepayments.

                  (a) The Borrower may, upon at least two Business Days prior
         written notice to Administrative Agent stating the proposed date and
         aggregate principal amount of the prepayment, prepay the outstanding
         principal amount of any Advances in whole or in part, together with
         accrued interest to the date of such prepayment on the principal amount
         prepaid without premium or penalty other than any Consequential Loss;
         provided, however, that in the case of a prepayment of a Base Advance,
         the notice of prepayment may be given by telephone by 10:00 a.m. on the
         date of prepayment. Each partial prepayment shall, in the case of Base
         Advances, be in an aggregate principal amount of not less than $500,000
         or a larger integral multiple of $50,000 in excess thereof (or, with
         respect to a Swingline Advance, in the full amount of such Swingline
         Advance) and, in the case of LIBOR Advances, be in an aggregate
         principal amount of not less than $5,000,000 or a larger integral
         multiple of $100,000 in excess thereof. If any notice of prepayment is
         given, the principal amount stated therein, together with accrued
         interest on the amount prepaid and the amount, if any, due under
         Section 2.12 and Section 2.14 hereof, shall be due and payable on the
         date specified in such notice unless the Borrower revokes its notice,
         provided that, if the Borrower revokes its notice of prepayment prior
         to such date specified, the Borrower shall reimburse the Administrative
         Agent for the account of all Lenders for all Consequential Losses
         suffered by each Lender as a result of the Borrower's failure to
         prepay. A certificate of each Lender claiming compensation under this
         Section 2.04(a), setting forth in reasonable detail the calculation of
         the additional amount or amounts to be paid to it hereunder shall be
         presumptive evidence of the validity of such claim.



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                  (b) No prepayments of Revolver Advances made solely pursuant
         to this Section 2.04 shall cause the Commitment to be reduced.
         Prepayments of Term Loan A Advances and Term Loan B Advances may not be
         reborrowed. All prepayments made hereunder shall be allocated in
         accordance with the terms and conditions of Section 2.13(f) hereof. All
         prepayments made pursuant to this Section 2.04 (other than to the
         Swingline Loan) shall be first applied to Base Advances then to LIBOR
         Advances.

         SECTION 7. Amendment of Section 2.05(e). Section 2.05(e) of the Credit
Agreement shall be deleted in its entirety and the following Section 2.05(e)
shall be substituted in its stead:

                  (e) Mandatory Prepayments, Generally. Unless otherwise
         directed by the Borrower, any prepayments made pursuant to this Section
         2.05 (other than prepayments applied to Swingline Advances) shall be
         first applied to Base Advances and then to LIBOR Advances, without
         premium or penalty, except the Borrower must pay together with any such
         prepayments, any Consequential Losses. Application of all payments and
         prepayments shall be applied in accordance with the terms of Section
         2.13(f) hereof.

         SECTION 8. Amendment of Section 2.06(e). Section 2.06(e) of the Credit
Agreement shall be deleted in its entirety and the following Section 2.06(e)
shall be substituted in its stead:

                  (e) Repayments, Generally. Any repayments made pursuant to
         this Section 2.06 (other than repayments applied to Swingline Advances)
         shall be first applied to Base Advances and then to LIBOR Advances in
         the order of maturity, without premium or penalty, except the Borrower
         must pay together with any such prepayments, any Consequential Losses.
         All repayments shall be allocated among the Loans in accordance with
         the terms of Section 2.13(f) hereof.

         SECTION 9. Amendment of Section 2.07. Section 2.07 of the Credit
Agreement shall be deleted in its entirety and the following Section 2.07 shall
be substituted in its stead:

                  2.07. Interest. Subject to Section 2.08 and Section 11.08
         hereof, the Borrower shall pay interest on the unpaid principal amount
         of each Advance from the date of such Advance until such principal
         shall be paid in full, at the following rates per annum, in each case
         as selected by the Borrower in accordance with the terms of Section
         2.02 hereof, and provided that Swingline Advances shall always bear
         interest at the Swingline Rate:

                           (a) Base Advances. Base Advances shall bear interest
                  at a rate per annum equal to the Base Rate as in effect from
                  time to time. If the amount of interest payable in respect of
                  any interest computation period is reduced to the Highest
                  Lawful Rate and the amount of interest payable in respect of
                  any subsequent interest computation period would be less than
                  Maximum Amount, then the amount of interest payable in respect
                  of such subsequent


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                  interest computation period shall be automatically increased
                  to the Maximum Amount; provided that at no time shall the
                  aggregate amount by which interest paid has been increased
                  pursuant to this sentence exceed the aggregate amount by which
                  interest has been reduced pursuant to this sentence.

                           (b) LIBOR Advances. LIBOR Advances shall bear
                  interest at the rate per annum equal to the LIBOR Rate
                  applicable to such Advance.

                           (c) Payment Dates. Accrued and unpaid interest on
                  Base Advances shall be paid quarterly in arrears on each
                  Quarterly Date and on the First Maturity Date with respect to
                  Advances under the Revolver Loan and the Term Loan A and the
                  Final Maturity Date with respect to Advances made under the
                  Term Loan B. Accrued and unpaid interest in respect of each
                  LIBOR Advance shall be paid on the last day of the appropriate
                  Interest Period and on the date of any prepayment or repayment
                  of such Advance; provided, however, that if any Interest
                  Period for a LIBOR Advance exceeds three months, interest
                  shall also be paid on the date which falls three months after
                  the beginning of such Interest Period.

                           (d) Swingline Advances. Swingline Advances shall bear
                  interest at a rate per annum equal to the Swingline Rate as in
                  effect from time to time. If the amount of interest payable in
                  respect of any interest computation period is reduced to the
                  Highest Lawful Rate and the amount of interest payable in
                  respect of any subsequent interest computation period would be
                  less than Maximum Amount, then the amount of interest payable
                  in respect of such subsequent interest computation period
                  shall be automatically increased to the Maximum Amount;
                  provided that at no time shall the aggregate amount by which
                  interest paid has been increased pursuant to this sentence
                  exceed the aggregate amount by which interest has been reduced
                  pursuant to this sentence. The Borrower shall pay interest on
                  the outstanding principal amount of such Swingline Advance,
                  from the date such Swingline Advance is made until it is due
                  (whether at maturity, by reason of acceleration or otherwise)
                  and repaid, at an interest rate per annum equal to the
                  Swingline Rate. Accrued and unpaid interest on Swingline
                  Advances shall be paid quarterly in arrears on each Quarterly
                  Date, on any rollover or extinguishment of any Swingline
                  Advance and on the First Maturity Date.

         SECTION 10. Amendment of Section 2.09(a)(i). Section 2.09(a)(i) of the
Credit Agreement shall be deleted in its entirety and the following Section
2.09(a)(i) shall be substituted in its stead:

                                 (i) elect to convert, on any Business Day, all
                  or any portion of outstanding Base Advances, except Base
                  Advances that are Swingline Advances (in an aggregate amount
                  not less than $500,000 or an integral multiple of $50,000 in
                  excess thereof) into LIBOR Advances; or


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         SECTION 11. Amendment of Section 2.13(f) and Addition of Section
2.13(g). Section 2.13(f) of the Credit Agreement shall be deleted in its
entirety and the following Section 2.13(f) shall be substituted in its stead,
and a new Section 2.13(g) shall be added to the end of Section 2.13 of the
Credit Agreement as set forth below:

                  (f) Notwithstanding anything to the contrary herein or in any
         Loan Paper, to the extent the Borrower makes any voluntary prepayment,
         or voluntary reduction of the Commitment under Sections 2.04 or 2.11
         hereof, or any mandatory prepayment, or mandatory reduction of the
         Commitment under Sections 2.05 and 2.11 hereof, then such reduction of
         the Commitment or such prepayment shall be applied as follows:

                           (i) so long as there exists no Default or Event of
                  Default, all voluntary Commitment reductions and all voluntary
                  repayments and prepayments shall be applied as directed by the
                  Borrower, and in the absence of direction by the Borrower,
                  shall be deemed to prepay and reduce, respectively (1) the
                  Commitment and the Swingline Loan and the Revolver Loan, until
                  the Commitment has been reduced to zero and the outstandings
                  under the Swingline Loan have been repaid in full and the
                  outstandings under the Revolver Loan have been repaid in full
                  (the Swingline Advances to be repaid in full prior to any
                  repayment of the Revolver Advances), then (2) the Term Loan A
                  and the Term Loan B, pro rata, until all outstanding Term Loan
                  A Advances and Term Loan B Advances have been repaid in full
                  and (3) to all remaining outstanding and unpaid Obligations;
                  provided that, so long as there exists no Default or Event of
                  Default, each Lender having a Term Loan B Specified Percentage
                  in excess of zero may elect to decline all voluntary
                  prepayments made or allocated to Term Loan B in accordance
                  with the terms of this Agreement, in which case such declined
                  prepayments shall be allocated to the Revolver Loan and the
                  Term Loan A pro rata;

                           (ii) so long as there exists no Default or Event of
                  Default, all mandatory Commitment reductions and all mandatory
                  repayments and prepayments shall be applied first to repay any
                  Swingline Advances and then pro rata among the Revolver Loan,
                  the Term Loan A and the Term Loan B, and then to all remaining
                  outstanding Obligations; provided that, so long as there
                  exists no Default or Event of Default, each Lender having a
                  Term Loan B Specified Percentage in excess of zero may elect
                  to decline all mandatory prepayments made or allocated to Term
                  Loan B in accordance with the terms of this Agreement, in
                  which case such declined prepayments shall be allocated to the
                  Revolver Loan and the Term Loan A pro rata;

                           (iii) if there exists a Default or Event of Default,
                  all mandatory and voluntary Commitment reductions and
                  mandatory and voluntary repayments and prepayments shall be
                  applied first to any outstanding Swingline Advances and then
                  pro rata among the Revolver Loan, the Term Loan A and the Term
                  Loan B, and then to all remaining outstanding Obligations; and


                                      -10-
<PAGE>   11
                           (iv) all Term Loan A and Term Loan B repayments and
                  prepayments shall be applied to installments due thereunder in
                  the inverse order of maturity, and all repayments and
                  prepayments, and reductions to the Commitment shall not affect
                  the mandatory commitment reduction schedule set forth in
                  Section 2.11(b) hereof.

                  (g) At all times prior to the Lenders making a Revolver
         Advance pursuant to Section 2.02(h) hereof, the Administrative Agent
         shall distribute all payments in respect of the Swingline Advances to
         the Swingline Bank. At such time, if any, that the Lenders make a
         Revolver Advance pursuant to Section 2.02(h) hereof, the Administrative
         Agent shall distribute all payments in respect of the Swingline
         Advances to the Lenders in accordance with the respective Revolver
         Specified Percentages.

         SECTION 12. Amendment of Section 2.15. Section 2.15 of the Credit
Agreement shall be deleted in its entirety and the following Section 2.15 shall
be substituted in its stead:

                  2.15. Use of Proceeds. The proceeds of all Revolver Advances
         and Swingline Advances borrowed hereunder shall be solely used in
         connection with the acquisition of assets in accordance with the terms
         of Section 1008(v) of the Indenture, such that all Revolver Advances
         and Swingline Advances constitute in each case, Acquisition Debt
         or"Purchase Money Secured Debt" (as defined in the Indenture) in
         accordance with the terms of the Indenture, the other Parent Senior
         Notes Documentation and permitted fully secured indebtedness under all
         Second Parent Issuance Documentation. The proceeds of the initial Term
         Loan B Advance and all Term Loan A Advances shall be available (and the
         Borrower shall use such proceeds) solely (i) with respect to the
         initial Term Loan B Advance and any Term Loan A Advance made on the
         Closing Date only, to refinance existing indebtedness of the Borrower,
         (ii) for Permitted Acquisitions, (iii) for Capital Expenditures
         permitted under the terms of this Agreement, (iv) for working capital
         and (v) for other lawful corporate purposes. Notwithstanding the
         preceding sentences of this Section 2.15, any Revolver Advance that
         constitutes a Qualified Facility Revolver Advance shall be available
         (and the Borrower shall use such proceeds) solely (i) for Permitted
         Acquisitions, (ii) for Capital Expenditures permitted under the terms
         of this Agreement, (iii) for working capital and (iv) for other lawful
         corporate purposes.

         SECTION 13. Amendment of Section 3.01. Section 3.01 of the Credit
Agreement shall be deleted in its entirety and the following Section 3.01 shall
be substituted in its stead:

                  3.01. Issuance of Letters of Credit. Letters of Credit issued
         under the Original Credit Agreement and described on Schedule 3.01
         hereto shall be deemed, for the purposes of this Agreement, to be
         issued hereunder, and each such Letter of Credit shall be treated
         accordingly. The Borrower shall give the Administrative Agent not less
         than five Business Days prior written notice of a request for the
         issuance of a Letter of Credit, and the Administrative Agent shall
         promptly notify each Lender of


                                      -11-
<PAGE>   12
         such request. Upon receipt of the Borrower's properly completed and
         duly executed Applications, and subject to the terms of such
         Applications and to the terms of this Agreement ( this Agreement
         governing all conflicting provisions), the Administrative Agent agrees
         to issue Letters of Credit on behalf of the Borrower in an aggregate
         face amount not in excess of the Letter of Credit Commitment, each
         denominated in Dollars and each for sight drawings only. No Letter of
         Credit shall have a maturity extending beyond the earliest of (i) the
         fifth Business Day prior to the First Maturity Date, or (ii) one year
         from the date of its issuance, or (iii) such earlier date as may be
         required to enable the Borrower to satisfy its repayment obligations
         under Section 2.06 hereof (including, without limitation, such
         repayment obligations resulting from a decrease in the Commitment
         required by Section 2.11 hereof). Subject to such maturity limitations
         and so long as no Default or Event of Default has occurred and is
         continuing or would result from the renewal of a Letter of Credit, the
         Letters of Credit may be renewed by the Administrative Agent in its
         discretion. The Lenders shall participate ratably in all rights and
         obligations of the Administrative Agent under the Letters of Credit and
         in any unreimbursed draws under any Letter of Credit in their Revolver
         Specified Percentages. The amount of the Letters of Credit issued and
         outstanding and the unpaid reimbursement obligations of the Borrower
         for such Letters of Credit shall reduce the amount of Commitment
         available, so that at no time shall the sum of (i) all outstanding
         Revolver Advances in the aggregate, plus (ii) all outstanding Swingline
         Advances in the aggregate, plus (iii) the aggregate face amount of all
         outstanding Letters of Credit, plus (iv) (without duplication) all
         outstanding reimbursement obligations related to Letters of Credit,
         exceed $235,000,000 (as such amount has been or may be increased by
         Section 2.18 hereof, and as may be reduced by Section 2.11 hereof), and
         at no time shall the sum of all Revolver Advances made by any Lender
         (except the Canada Lender), plus any such Lender's ratable share of
         amounts available to be drawn under the Letters of Credit and the
         unpaid reimbursement obligations of the Borrower in respect of such
         Letters of Credit exceed such Lender's Revolver Specified Percentage of
         the Commitment, provided that, with respect to the Canada Lender, at no
         time shall the sum of all Revolver Advances made by the Canada Lender
         plus its ratable share of amounts available to be drawn under the
         Letters of Credit and the unpaid reimbursement obligations of the
         Borrower in respect of such Letters of Credit exceed an amount equal to
         the difference between its Revolver Specified Percentage of the
         Commitment, minus the Canada Indebtedness Amount.

         SECTION 14. Amendment of Section 4.02(f) and Section 4.02(g). Section
4.02(f) and Section 4.02(g) of the Credit Agreement shall be deleted in their
entirety and the following Section 4.02(f) and 4.02(g) shall be substituted in
their stead:

                  (f) In the case of any Advance under the Revolver Loan, the
         aggregate outstanding Revolver Advances, after giving effect to any
         such proposed Revolver Advance, shall not exceed the Commitment, and in
         the case of any Advance under the Swingline Loan, the aggregate
         outstanding Swingline Advances, after giving effect to any such
         proposed Swingline Advance, shall not exceed the Swingline Commitment;
         and


                                      -12-
<PAGE>   13
                  (g) In the case of each and every Advance under the Loan, the
         Borrower, by making its borrowing request hereunder, or requesting the
         issuance of any Letter of Credit, will provide a certificate to the
         Administrative Agent containing (i) a representation and warranty to
         the Administrative Agent and each Lender that the proceeds of such
         Advance shall be used in accordance with the terms of Section 2.15
         hereof, and (ii) a representation and calculation that with respect to
         each Revolver Advance that is not a Qualified Facility Revolver Advance
         and each Swingline Advance, such Advance will constitute Acquisition
         Debt in accordance with the terms of the Indenture and that such
         acquisition is a nonleveraging event, in accordance with the terms of
         the Indenture, the Parent Senior Notes Documentation (with supporting
         calculations in reasonable detail acceptable to the Administrative
         Agent with respect thereto).

         SECTION 15. Amendment of Section 10.03. Section 10.03 of the Credit
Agreement shall be deleted in its entirety and the following Section 10.03 shall
be substituted in its stead:

                  10.03. Bank of America, N.A. and Affiliates. With respect to
         its portion of the Commitment, its Advances, the Canada Indebtedness,
         the Swingline Loan and any Loan Papers, Bank of America, N.A. has the
         same Rights under this Agreement as any other Lender and may exercise
         the same as though it were not Administrative Agent. Bank of America,
         N.A. and its Affiliates may accept deposits from, lend money to, act as
         trustee under indentures of, and generally engage in any kind of
         business with, any Obligor, any Affiliate thereof, and any Person who
         may do business therewith, all as if Bank of America, N.A. were not
         Administrative Agent and without any duty to account therefor to any
         Lender.

         SECTION 16. Amendment of Section 10.06. Section 10.06 of the Credit
Agreement shall be deleted in its entirety and the following Section 10.06 shall
be substituted in its stead:

                  10.06. Successor Administrative Agent. Administrative Agent
         may resign at any time by giving written notice thereof to Lenders and
         the Borrower, and may be removed at any time with or without cause by
         the action of all Lenders (other than Administrative Agent, if it is a
         Lender). If the Administrative Agent also then serves in the capacity
         of the Swingline Bank or the Letter of Credit issuing bank, such
         resignation or removal shall constitute resignation or removal of the
         Swingline Bank and the Administrative Agent in its capacity as Letter
         of Credit issuing bank and the successor Administrative Agent shall
         serve in the capacity of the Swingline Bank and the Letter of Credit
         issuing bank. Upon any such resignation, Majority Lenders shall have
         the right to appoint a successor Administrative Agent. If no successor
         Administrative Agent shall have been so appointed and shall have
         accepted such appointment within thirty days after the retiring
         Administrative Agent's giving of notice of resignation, then the
         retiring Administrative Agent may, on behalf of Lenders, appoint a
         successor Administrative Agent, which shall be a commercial bank
         organized under the Laws of the United States of America or of any
         State thereof and having a combined capital and surplus of at least
         $50,000,000. Upon the acceptance


                                      -13-
<PAGE>   14
         of any appointment as Administrative Agent hereunder by a successor
         Administrative Agent, such successor Administrative Agent shall
         thereupon succeed to and become vested with all the Rights and duties
         of the retiring Administrative Agent, and the retiring Administrative
         Agent shall be discharged from its duties and obligations under the
         Loan Papers, provided that if the retiring or removed Administrative
         Agent is unable to appoint a successor Administrative Agent,
         Administrative Agent shall, after the expiration of a sixty day period
         from the date of notice, be relieved of all obligations as
         Administrative Agent hereunder. Notwithstanding any Administrative
         Agent's resignation or removal hereunder, the provisions of this
         Article shall continue to inure to its benefit as to any actions taken
         or omitted to be taken by it while it was Administrative Agent under
         this Agreement.

         SECTION 17. Addition of Last Sentence to Section 11.01. A new last
sentence shall be added to the end of Section 11.01 of the Credit Agreement as
follows:

         No amendment, waiver, or consent shall affect the Rights or duties of
         Swingline Bank or the Administrative Agent in its capacity as issuer of
         any Letter of Credit under any Loan Papers, unless it is in writing and
         signed by the Swingline Bank or the Administrative Agent in addition to
         the requisite number of Lenders.

         SECTION 18. Amendment of Section 11.05. Section 11.05 of the Credit
Agreement shall be deleted in its entirety and the following Section 11.05 shall
be substituted in its stead:

                  11.05. Sharing of Payments. If, after and during the
         continuance of any Event of Default, any Lender shall obtain any
         payment (whether voluntary, involuntary, through the exercise of any
         Right of set-off, or otherwise) on account of its Advances in excess of
         its pro rata share of payments made by the Borrower in accordance with
         such Lender's Total Specified Percentage (except payments to the
         Swingline Bank made to repay Swingline Advances), such Lender shall
         forthwith purchase participations in Advances made by the other Lenders
         as shall be necessary to share the excess payment pro rata in
         accordance with each Lender's Total Specified Percentage with each of
         them; provided, however, that if any of such excess payment is
         thereafter recovered from the purchasing Lender, its purchase from each
         Lender shall be rescinded and each Lender shall repay the purchase
         price to the extent of such recovery together with a pro rata share of
         any interest or other amount paid or payable by the purchasing Lender
         in respect of the total amount so recovered. The Borrower agrees that
         any Lender so purchasing a participation from another Lender pursuant
         to this Section 11.05 may, to the fullest extent permitted by Law,
         exercise all its Rights of payment (including the Right of set-off)
         with respect to such participation as fully as if such Lender were the
         direct creditor of the Borrower in the amount of such participation.

         SECTION 19. Addition of Exhibit A-4. Exhibit A-4 attached to this
Second Amendment shall be added to the Credit Agreement and attached as Exhibit
A-4 to the Credit Agreement.


                                      -14-
<PAGE>   15
         SECTION 20. Conditions Precedent. This Second Amendment shall not be
effective until all proceedings of the Borrower taken in connection with this
Second Amendment and the transactions contemplated hereby shall be satisfactory
in form and substance to the Administrative Agent and Lenders, and the
Administrative Agent and Lenders shall have each received:

                  (a) copies of resolutions authorizing the execution, delivery
         and performance of this Second Amendment by the Borrower, the Parent,
         and their Subsidiaries and legal opinions by counsel in form and
         substance satisfactory to the Administrative Agent regarding the due
         execution, delivery and performance of this Second Amendment and the
         legality, validity and the enforceability thereof;

                  (b) the Borrower shall have delivered to the Administrative
         Agent a fully executed and completed Swingline Note; and

                  (c) such other documents, instruments, and certificates, in
         form and substance satisfactory to the Administrative Agent, as the
         Administrative Agent shall deem necessary or appropriate in connection
         with this Second Amendment and the transactions contemplated hereby.

         SECTION 21. Representations and Warranties. The Borrower represents and
warrants to the Lenders and the Administrative Agent that (a) this Second
Amendment constitutes its legal, valid, and binding obligations, enforceable in
accordance with the terms hereof (subject as to enforcement of remedies to any
applicable bankruptcy, reorganization, moratorium, or other laws or principles
of equity affecting the enforcement of creditors' rights generally), (b) there
exists no Event of Default or Default under the Credit Agreement both before and
after giving effect to this Second Amendment, (c) its representations and
warranties set forth in the Credit Agreement and other Loan Papers are true and
correct on the date hereof both before and after giving effect to this Second
Amendment, (d) it has complied with all agreements and conditions to be complied
with by it under the Credit Agreement and the other Loan Papers by the date
hereof, (e) the Credit Agreement, as amended hereby, and the other Loan Papers
remain in full force and effect, and (f) no notice to, or consent of, any Person
is required under the terms of any agreement of the Borrower in connection with
the execution of this Second Amendment.

         SECTION 22. Further Assurances. The Borrower shall execute and deliver
such further agreements, documents, instruments, and certificates in form and
substance satisfactory to the Administrative Agent, as the Administrative Agent
or any Lender may deem necessary or appropriate in connection with this Second
Amendment.

         SECTION 23. Counterparts. This Second Amendment and the other Loan
Papers may be executed in any number of counterparts, all of which taken
together shall constitute one and the same instrument. In making proof of any
such agreement, it shall not be necessary to produce or account for any
counterpart other than one signed by the party against which enforcement is
sought.

         SECTION 24. ENTIRE AGREEMENT. THIS AGREEMENT AND THE OTHER LOAN PAPERS
REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY
EVIDENCE OF PRIOR, CONTEMPORANEOUS OR




                                      -15-
<PAGE>   16
SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL
AGREEMENTS BETWEEN THE PARTIES.

         SECTION 25. GOVERNING LAW. (a) THIS AGREEMENT AND ALL LOAN PAPERS SHALL
BE DEEMED CONTRACTS MADE UNDER THE LAWS OF TEXAS AND SHALL BE CONSTRUED AND
ENFORCED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF TEXAS, EXCEPT TO THE
EXTENT (A) FEDERAL LAWS GOVERN THE VALIDITY, CONSTRUCTION, ENFORCEMENT AND
INTERPRETATION OF ALL OR ANY PART OF THIS AGREEMENT AND ALL LOAN PAPERS OR (B)
STATE LAW GOVERNS UCC COLLATERAL INTERESTS FOR PROPERTIES OF THE BORROWER AND
THE SUBSIDIARIES OUTSIDE THE STATE OF TEXAS. WITHOUT EXCLUDING ANY OTHER
JURISDICTION, THE BORROWER AND EACH SUBSIDIARY AGREES THAT THE COURTS OF TEXAS
WILL HAVE JURISDICTION OVER PROCEEDINGS IN CONNECTION HEREWITH.

         (b) THE BORROWER AND EACH SUBSIDIARY HEREBY WAIVES PERSONAL SERVICE OF
ANY LEGAL PROCESS UPON IT. IN ADDITION, THE BORROWER AND EACH SUBSIDIARY AGREES
THAT SERVICE OF PROCESS MAY BE MADE UPON IT BY REGISTERED MAIL (RETURN RECEIPT
REQUESTED) DIRECTED TO THE BORROWER AT ITS ADDRESS DESIGNATED FOR NOTICE UNDER
THIS AGREEMENT AND SERVICE SO MADE SHALL BE DEEMED TO BE COMPLETED UPON RECEIPT
BY THE BORROWER. NOTHING IN THIS SECTION SHALL AFFECT THE RIGHT OF THE
ADMINISTRATIVE AGENT OR ANY LENDER TO SERVE LEGAL PROCESS IN ANY OTHER MANNER
PERMITTED BY LAW.

         SECTION 26. WAIVER OF JURY TRIAL. TO THE MAXIMUM EXTENT PERMITTED BY
LAW, EACH PARTY HERETO, AND EACH LENDER HEREBY WAIVES ANY RIGHT THAT IT MAY HAVE
TO A TRIAL BY JURY OF ANY DISPUTE (WHETHER A CLAIM IN TORT, CONTRACT, EQUITY, OR
OTHERWISE) ARISING UNDER OR RELATING TO THIS AGREEMENT, THE OTHER LOAN PAPERS,
OR ANY RELATED MATTERS, AND AGREES THAT ANY SUCH DISPUTE SHALL BE TRIED BEFORE A
JUDGE SITTING WITHOUT A JURY.



                                      -16-
<PAGE>   17
         IN WITNESS WHEREOF, this Second Amendment to Fifth Amended and Restated
Credit Agreement is executed as of the date set forth above.

THE BORROWER:                    PINNACLE TOWERS INC.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


ADMINISTRATIVE AGENT:
                                 BANK OF AMERICA, N.A.,
                                 as Administrative Agent


                                 -----------------------------------------------
                                 By:   Roselyn M. Drake
                                 Its:  Vice President

LENDERS:

                                 BANK OF AMERICA, N.A., individually as a Lender



                                 -----------------------------------------------
                                 By:   Roselyn M. Drake
                                 Its:  Vice President

                                 BANKBOSTON, N.A.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------




                                      -17-
<PAGE>   18
                                 BANKERS TRUST COMPANY


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 SOCIETE GENERALE


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 UNION BANK OF CALIFORNIA, N.A.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 KEY CORPORATE CAPITAL INC.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 COBANK, ACB


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------



                                      -18-
<PAGE>   19
                                 CREDIT LYONNAIS NEW YORK BRANCH


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 THE BANK OF NOVA SCOTIA


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 DRESDNER BANK AG NEW YORK & GRAND CAYMAN
                                 BRANCHES



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 MERCANTILE BANK NATIONAL ASSOCIATION



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 U.S. BANK NATIONAL ASSOCIATION



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------





                                      -19-
<PAGE>   20
                                 CREDIT LOCAL DE FRANCE - NEW YORK AGENCY



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------

                                 IBM CREDIT CORPORATION


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 THE CIT GROUP/EQUIPMENT FINANCING, INC.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 ALLFIRST BANK


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 CITY NATIONAL BANK


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------



                                      -20-
<PAGE>   21
                                 RAYMOND JAMES BANK, FSB


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 HELLER FINANCIAL, INC.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------

                                 PILGRIM PRIME RATE TRUST

                                 By:   Pilgrim Investment, Inc.,
                                       as its investment manager


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 PPM SPYGLASS FUNDING TRUST


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 MORGAN STANLEY DEAN WITTER PRIME INCOME TRUST



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------



                                      -21-
<PAGE>   22
                                 KZH ING-1 LLC


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 KZH ING-2 LLC


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------

                                 SEQUILS-ING I (HBDGM), LTD.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 TORONTO DOMINION (NEW YORK), INC.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


                                 SEQUILS PILGRIM I, LTD.



                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------



                                      -22-
<PAGE>   23
                                 WEBSTER BANK


                                 -----------------------------------------------
                                 By:
                                       -----------------------------------------
                                 Its:
                                       -----------------------------------------


Accepted and Agreed as
of October ___, 1999:

PINNACLE HOLDINGS, INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------


COVERAGE PLUS ANTENNA SYSTEMS, INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------


TOWER SYSTEMS, INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------


RADIO STATION WGLD, INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------



WEO TOWER INC.




                                      -23-
<PAGE>   24
By:
        -------------------------------------------
Its:
        -------------------------------------------


ICB TOWERS, LLC



By:
        -------------------------------------------
Its:
        -------------------------------------------


AIRCOMM OF AVON, LLC



By:
        -------------------------------------------
Its:
        -------------------------------------------


HIGH POINT MANAGEMENT CO., INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------


TOWER TECHNOLOGY CORPORATION OF JACKSONVILLE



By:
        -------------------------------------------
Its:
        -------------------------------------------



                                      -24-
<PAGE>   25
ARROWHEAD CORPORATION OF DELHI



By:
        -------------------------------------------
Its:
        -------------------------------------------


COASTAL ANTENNA'S INC.



By:
        -------------------------------------------
Its:
        -------------------------------------------


MARMAC INDUSTRIES INCORPORATED



By:
        -------------------------------------------
Its:
        -------------------------------------------



                                      -25-