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                                                                    EXHIBIT 10.3

                                                                 EXECUTION COPY


                             CINGULAR WIRELESS LLC
                                SBC WIRELESS LLC
                            5565 GLENRIDGE CONNECTOR
                                   SUITE 2000
                             ATLANTA, GEORGIA 30342

                                                              November 14, 2002

Southern Towers, Inc.
SpectraSite Holdings, Inc.
and SpectraSite Communications, Inc.
c/o SpectraSite Communications, Inc.
100 Regency Forest Drive, Suite 400
Cary, North Carolina 27511

SBC Tower Holdings LLC
c/o SBC Communications Inc.
175 E. Houston
San Antonio, Texas 78205

         Re:      Amended and Restated Transaction Documents Amendment


Ladies and Gentlemen:

                  Reference is made to (i) that certain Transaction Documents
Amendment Letter Agreement, dated as of May 15, 2002, by and among SBC Wireless
LLC, SBC Tower Holdings LLC, Cingular Wireless LLC, SpectraSite Holdings, Inc.,
SpectraSite Communications, Inc. and Southern Towers, Inc. (the "Original
Unwind Side Letter") and (ii) those certain agreements and amendments thereto
identified and defined on Schedule A hereto (the "Transaction Documents").
Capitalized terms used and not defined herein shall have the respective
meanings ascribed thereto in the Agreement to Sublease (as amended and modified
from time to time).

                  In connection with the November Agreement, dated as of the
date hereof, by and among certain of the parties hereto and certain of their
respective affiliates (the "November Agreement"), the parties hereto desire to
amend and restate the Original Unwind Side Letter as follows (this letter
agreement, the "Amended and Restated Unwind Side Letter"):

                  1.       Transaction Documents. Subject to the provisions of
this Amended and Restated Unwind Side Letter and notwithstanding anything to
the contrary contained in the Transaction Documents, the parties agree to and
acknowledge the following modifications to the Transaction Documents. Except as
expressly amended hereby or by other documents executed on or about or prior to
the date hereof and


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described on Schedule C, the Transaction Documents shall remain in full force
and effect.

                  (a)      The parties hereto agree that in accordance with
         Section 16.19 of the Agreement to Sublease and for good and valuable
         consideration including all provisions set forth herein, on the
         Effective Date (as defined herein) the Agreement to Sublease is hereby
         amended and modified as follows:

                           (i)      The definition of "Site" is hereby amended
                                    to delete from said definition and from
                                    Annex A to the Agreement to Sublease 187
                                    sites located in California and Nevada
                                    identified on the attached Schedule B (the
                                    "California and Nevada Unclosed Sites").
                                    Without limiting the foregoing, the
                                    California and Nevada Unclosed Sites shall
                                    not be deemed to constitute Existing Sites,
                                    Excluded Sites or Included Sites thereunder
                                    or under any Transaction Document.

                           (ii)     Notwithstanding anything to the contrary in
                                    Amendment No. 2 to the Agreement to
                                    Sublease, dated as of November 14, 2001
                                    ("Amendment No. 2"), in no event shall more
                                    than 3,306 Sites become Included Sites
                                    under the Agreement to Sublease. As of the
                                    date hereof there are 2,706 Included Sites
                                    under the Agreement to Sublease.
                                    Notwithstanding anything to the contrary in
                                    Amendment No. 2, with respect to the
                                    remaining 600 Sites which may become
                                    Included Sites: (1) the Transfer Dates
                                    shall be as follows: May 15, 2003; August
                                    15, 2003; November 17, 2003; February 16,
                                    2004; May 17, 2004; and August 16, 2004;
                                    (each, a "Transfer Date") and "Final
                                    Transfer Date" shall mean the earlier to
                                    occur of (x) August 16, 2004 and (y) that
                                    date of the Transfer Closing at which 3,306
                                    Sites have become Included Sites (the
                                    closing occurring on the Final Transfer
                                    Date, the "Final Transfer Closing") and (2)
                                    the parties shall use commercially
                                    reasonable efforts to include on each
                                    Transfer Date 100 Transfer Sites selected
                                    by the parties in accordance with Section
                                    4.1(e)(i) of the Agreement to Sublease to
                                    become Included Sites and in any event
                                    shall not be required to include on any
                                    such Transfer Date in excess of 100
                                    Transfer Sites to become Included Sites
                                    (except that such 100


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                                    Transfer Sites limitation shall not apply
                                    on the Final Transfer Date).

                           (iii)    Article XV of the Agreement to Sublease is
                                    hereby deleted therefrom and shall have no
                                    further force or effect.

                           (iv)     Immediately prior to the exchange of Parent
                                    Stock for the consideration to be issued by
                                    TowerCo Parent in connection with a
                                    restructuring of the debt and capital
                                    structure of TowerCo Parent (on
                                    substantially the terms set forth in
                                    Exhibit 2 attached to the November
                                    Agreement, to be effectuated under a
                                    chapter 11 case under 11 U.S.C. ss.ss. 101
                                    et seq. filed by Parent) (the
                                    "Consideration"), TowerCo Parent shall
                                    issue 12,144,381 shares of Parent Stock
                                    (which number of shares is subject to
                                    appropriate adjustment in the event of any
                                    stock dividends, splits, reverse splits,
                                    combinations or subdivisions occurring
                                    prior to such issuance) to SBC Tower
                                    Holdings LLC ("SBC TowerCo") in full
                                    satisfaction of its obligation to pay (x)
                                    the Stock Portion of the prepaid Rent
                                    pursuant to Sections 3.2(a) and (b) of the
                                    Agreement to Sublease for any and all of
                                    the remaining 600 Transfer Sites and (y)
                                    any adjustments with respect to the Parent
                                    Stock required under Sections 3.2(c)-(i) of
                                    the Agreement to Sublease. The parties
                                    agree and acknowledge that with respect to
                                    each Transfer Closing, Tower Co and TowerCo
                                    Parent shall only be obligated to pay the
                                    Cash Portion of the prepaid Rent with
                                    respect to each Transfer Site that becomes
                                    an Included Site at a Transfer Closing and
                                    that TowerCo and TowerCo Parent shall have
                                    no further obligations to issue any Parent
                                    Stock in connection with the transactions
                                    contemplated by the Agreement to Sublease.
                                    The parties acknowledge and agree that the
                                    Parent Stock issued to SBC TowerCo
                                    hereunder shall be the Parent Stock
                                    outstanding prior to the effective date of
                                    the Seller Parent's Plan of Reorganization
                                    (as defined in the November Agreement) and
                                    that such Parent Stock issued to SBC
                                    TowerCo hereunder, together with all Parent
                                    Stock previously issued to SBC TowerCo,
                                    shall then be exchanged into Consideration
                                    under the Seller Parent's Plan of
                                    Reorganization in the


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                                    same manner and pro rata percentage as all
                                    other holders of Parent Stock receive in
                                    such exchange.

                  (b)      From and after the date hereof, all obligations and
         rights of the parties to the Site Marketing Agreement shall be
         terminated with respect to the California and Nevada Sites (as defined
         below), including, without limitation, the obligation and right of
         Marketer (as defined in the Site Marketing Agreement) to provide
         marketing services for the California and Nevada Sites and the right
         of the Marketer to receive fees and other compensation thereunder with
         respect to the California and Nevada Sites (whether or not Marketer
         has provided marketing services with respect thereto prior to the
         effective date of this letter agreement); provided, however, that the
         foregoing shall not constitute a release of, and the parties to the
         Site Marketing Agreement shall each retain, any other liability or
         obligation of such party to the extent arising out of events occurring
         or actions taken prior to the effective date of this letter agreement
         (including, without limitation, the parties' rights to indemnification
         as provided in Section 19 of the Site Marketing Agreement). For
         purposes hereof, the "California and Nevada Sites" are collectively
         all Sites located in California or Nevada.

                  (c)      The Lease and Sublease shall be amended to the
         extent and as provided in that certain Amended and Restated Consent
         and Modification Agreement dated as of the date hereof.

                  2.       Special Payment.

                  For and in consideration of the amendment to the Transaction
Documents outlined above, the various other agreements and undertakings of the
parties contained herein and the various agreements and undertakings of the
parties contained in the Amended and Restated Release and Acknowledgement (as
such term is defined in the Purchase Agreement), on the Effective Date, TowerCo
shall be obligated to pay to SBC TowerCo Seven Million Five Hundred Thousand
Dollars ($7,500,000) (the "Special Payment"). The parties acknowledge and agree
(i) that said obligation will be assigned to and assumed by CA/NV Tower
Holdings, LLC ("NewCo") pursuant to the Assignment and Assumption Agreement (as
such term is defined in the Purchase Agreement) and (ii) that such assignment
and assumption is hereby consented to and shall in no manner affect the Amended
and Restated Release and Acknowledgement by, between and among the parties
hereto executed contemporaneously herewith. The parties agree and acknowledge
that upon the consummation of the transactions contemplated by the Purchase
Agreement, none of the SCI Releasees (as such term is defined in the Amended
and Restated Release and Acknowledgement) shall have any obligation or
liability with respect to the fulfillment of NewCo's obligation to pay the
Special Payment, and that immediately after the closing of the transactions
contemplated by the Purchase Agreement, NewCo shall pay the Special Payment to
SBC TowerCo.


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                  3.       Binding Effect. This Amended and Restated Unwind
Letter shall be binding upon and shall inure to the benefit of the parties
hereto and their respective legal representatives, successors and assigns and
may not be modified or amended except by a written agreement executed by all
parties hereto.

                  4.       Counterparts. This Amended and Restated Unwind Side
Letter may be executed in several counterparts, each of which shall be deemed
an original, and all of such counterparts together shall constitute one and the
same instrument.

                  5.       Governing Law. The parties agree that this Amended
and Restated Unwind Side Letter shall be governed by and construed in all
respects in accordance with the laws of the State of New York, without regard
to its conflicts of law or choice of law principles.

                  6.       Severability. Any term or provision of this Amended
and Restated Unwind Side Letter which is invalid or unenforceable in any
jurisdiction shall, as to that jurisdiction, be ineffective to the extent of
such invalidity or unenforceability without rendering invalid or unenforceable
the remaining terms and provisions of this Amended and Restated Unwind Side
Letter in any other jurisdiction. If any provision of this Amended and Restated
Unwind Side Letter is so broad as to be unenforceable, the provision shall be
interpreted to be only so broad as is enforceable.

                  7.       Effectiveness. Except as provided in paragraph 1(b)
above, which shall be effective immediately, this Amended and Restated Unwind
Side Letter shall become effective upon the Closing (as defined in the Purchase
Agreement) of the transactions contemplated by the Purchase Agreement (the
"Effective Date"); provided that if the Purchase Agreement is terminated in
accordance with its terms prior to the Closing thereunder, this Amended and
Restated Unwind Side Letter shall terminate and be null and void.

                  8.       Entire Agreement. Except as otherwise expressly
provided herein, this Amended and Restated Unwind Side Letter constitutes the
entire agreement between the parties and supersedes the Original Unwind Side
Letter and all other prior agreements, understandings, representations and
warranties both written and oral, between the parties hereto with respect to
the subject matter hereof.


               [Remainder of this page intentionally left blank]


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                  Please confirm your acceptance of and agreement to the
foregoing by signing and returning the accompanying copy of this Amended and
Restated Unwind Side Letter, whereupon this Amended and Restated Unwind Side
Letter shall become binding on the parties hereto.


                                    CINGULAR WIRELESS LLC

                                    By: /s/ STEPHEN A. MCGAW
                                       ----------------------------------------
                                       Name: Stephen A. McGaw
                                       Title: Executive Vice President -
                                              Corporate Development

                                    SBC WIRELESS LLC

                                    By: STEPHEN A. MCGAW
                                       ----------------------------------------
                                       Name: Stephen A. McGaw
                                       Title: Executive Vice President -
                                              Corporate Development


The undersigned accept and agree to the
Foregoing, as of the date first written
above:

SBC TOWER HOLDINGS, LLC

By: /s/ JAMES S. KAHAN
   ----------------------------------------------
   Name: James S. Kahan
   Title: President

SPECTRASITE HOLDINGS, INC.

By: /s/ STEPHEN H. CLARK
   ----------------------------------------------
   Stephen H. Clark
   President and Chief Executive Officer

SOUTHERN TOWERS, INC.

By: /s/ STEPHEN H. CLARK
   ----------------------------------------------
   Stephen H. Clark
   President and Chief Executive Officer

SPECTRASITE COMMUNICATIONS, INC.

By: /s/ STEPHEN H. CLARK
   ----------------------------------------------
   Stephen H. Clark
   President and Chief Executive Officer


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