<PAGE>   1

                                                                   Exhibit 10.28



                   FIRST AMENDMENT TO PARTICIPATION AGREEMENT



         THIS FIRST AMENDMENT TO PARTICIPATION AGREEMENT (this "Amendment"),
dated as of June 4, 1999, is entered into by and among:

                  (1) NOVELLUS SYSTEMS, INC., a California corporation
         ("Lessee");

                  (2) LEASE PLAN NORTH AMERICA, INC., an Illinois corporation
         ("Head Lessor");

                  (3) ABN AMRO LEASING, INC., an Illinois corporation
         ("Lessor");

                  (4) Each of the financial institutions listed in Schedule I to
         the Participation Agreement referred to in Recital A below
         (collectively, the "Participants"); and

                  (5) ABN AMRO BANK N.V., as agent for the Participants (in such
         capacity, "Agent").


                                    RECITALS

         A. Lessee, Head Lessor, Lessor, Participants and Agent are parties to a
Participation Agreement dated as of August 31, 1998 (the "Participation
Agreement"), pursuant to which Lessor and Participants have provided to Lessee
two lease facilities (individually, "Facility 1" and "Facility 2" and,
collectively, the "Facilities").

         B. Lessee now has requested Head Lessor, Lessor, Participants and Agent
to amend the Participation Agreement and certain of the other Operative
Documents (as defined in the Participation Agreement) to (1) increase the amount
of Facility 2 by $20,000,000 and extend the availability period for Facility 2
by nine months to provide for the construction of a clean room (the "Clean
Room") as part of the New Improvements to the Tract 4 Land, and (2) permit the
purchase by Lessee from time to time of portions of the property under the
Facilities.

         C. Head Lessor, Lessor, Participants and Agent are willing so to amend
the Participation Agreement and the other Operative Documents upon the terms and
subject to the conditions set forth in this Amendment.


                                    AGREEMENT

         NOW, THEREFORE, in consideration of the above recitals and for other
good and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, Lessee, Head Lessor, Lessor, the Participants and Agent hereby
agree as follows:


<PAGE>   2

         1. DEFINITIONS, INTERPRETATION. All capitalized terms defined above and
elsewhere in this Amendment shall be used herein as so defined. Unless otherwise
defined herein, all other capitalized terms used herein shall have the
respective meanings given to those terms in the Participation Agreement, as
amended by this Amendment. The rules of construction set forth in Schedule 1.02
to the Participation Agreement shall, to the extent not inconsistent with the
terms of this Amendment, apply to this Amendment and are hereby incorporated by
reference.

         2. AMENDMENTS TO PARTICIPATION AGREEMENT. Subject to the satisfaction
of the conditions set forth in Paragraph 5 below, the Participation Agreement is
hereby amended as follows:

            (a) Subparagraph 2.01(d) is amended to read in its entirety as
follows:

                        (d) Amount Limitations. The amount of all advances made
            by Lessor hereunder (the "Advances") shall be subject to the
            following limitations:

                                    (i) The aggregate amount of all Advances
                        made by Lessor under Facility 1 shall not exceed the
                        lesser of (A) Twenty-Four Million Five Hundred Thousand
                        Dollars ($24,500,000) (the "Total Facility 1
                        Commitment") and (B) the Expiration Date Appraisal for
                        the Facility 1 Property;

                                    (ii) The aggregate amount of all Advances
                        made by Lessor under Facility 2 shall not exceed the
                        lesser of (A) One Hundred Eighty-Three Million Nine
                        Hundred Thousand Dollars ($183,900,000) (the "Total
                        Facility 2 Commitment") and (B) the Expiration Date
                        Appraisal for the Facility 2 Property; and

                                    (iii) The aggregate amount of all Advances
                        made by Lessor under both Facilities shall not exceed
                        Two Hundred Eight Million Four Hundred Thousand Dollars
                        ($208,400,000) (the "Total Commitment");

            Provided, however, that (1) the aggregate amount of all Advances
            made by Lessor under Facility 2 shall not exceed One Hundred
            Sixty-Three Million Nine Hundred Thousand Dollars ($163,900,000) and
            the aggregate amount of all Advances made by Lessor under both
            Facilities shall not exceed One Hundred Eighty-Eight Million Four
            Hundred Thousand Dollars ($188,400,000) until the first Business Day
            after Agent has received the following, each in form and substance
            satisfactory to Agent:

                                    (x) A copy of the final plans and
                        specifications for the Tract 4 Clean Room Improvements
                        (the "Tract 4 Clean Room Plans and Specifications"),
                        together with a certificate of the architect for the
                        Tract 4 Clean Room Improvements certifying that the
                        Tract 4 Clean Room Plans and Specifications are
                        complete;



                                       2
<PAGE>   3

                                    (y) A letter from Lessor stating that Lessor
                        has reviewed the Tract 4 Clean Room Plans and
                        Specifications and approved the revisions, amendments,
                        supplementations and modifications to the Plans and
                        Specifications reflected therein pursuant to Paragraph
                        3.02 of the Facility 2 Construction Agency Agreement;
                        and

                                    (z) A letter from the appraiser that
                        provided the Expiration Date Appraisal for the Facility
                        2 Property pursuant to the First Amendment to
                        Participation Agreement stating that such appraiser has
                        reviewed the Tract 4 Clean Room Plans and Specifications
                        and such plans and specifications do not alter the
                        appraisal of the Facility 2 Property set forth in such
                        Appraisal.

                  (b) Paragraph 7.04 is amended by (i) replacing the period at
         the end of subparagraph (c) thereof with a semi-colon and (ii) adding
         immediately prior to the first sentence following subparagraph (c) a
         proviso to read in its entirety as follows:

                  Provided, however, that, upon the exercise by Lessee of the
                  Partial Purchase Option under either Purchase Agreement in
                  accordance with Paragraph 2.02 of such Purchase Agreement,
                  Lessor (or Head Lessor in the case of either Head Lease) may
                  execute such documents, instruments and agreements (including
                  releases and/or amendments to the Operative Documents) as may
                  be reasonably necessary to release the Property to be
                  purchased pursuant to such Partial Purchase Option.

                  (c) Schedule I is amended by changing Part A(2) and Part A(3)
         thereof to read in their entirety as set forth in Attachment 1 hereto.

                  (d) Schedule 1.01 is amended as follows:

                           (i) The definition of the term "Credit Event" set
                  forth therein is changed to read in its entirety as follows:

                                    "Credit Event" shall mean the making of each
                           Advance, the selection of a new Rental Period or the
                           exercise of the Partial Purchase Option or Marketing
                           Option under either Purchase Agreement.

                           (ii) The definition of the term "Expiration Date
                  Appraisal" set forth therein is changed to read in its
                  entirety as follows:

                                    "Expiration Date Appraisal" shall mean (a)
                           with respect to the Facility 1 Property (or any
                           portion thereof) as of any date, an Appraisal that
                           assesses at such time the Fair Market Value of such
                           Property on the Scheduled Expiration Date and (b)
                           with respect to the Facility 2 Property (or any
                           portion thereof) as of any date, an Appraisal that
                           assesses at such time the Fair Market Value of such
                           Property on the Scheduled Expiration



                                       3
<PAGE>   4

                           Date and as improved in accordance with the Plans and
                           Specifications for the New Improvements (including
                           the plans and specifications for the Clean Room
                           approved by Lessor in the First Amendment to
                           Participation Agreement).

                           (iii) A new definition of the term "First Amendment
                  to Participation Agreement", reading in its entirety as
                  follows, is added thereto in the appropriate alphabetical
                  order:

                                    "First Amendment to Participation Agreement"
                           shall mean the First Amendment to Participation
                           Agreement dated as of June 4, 1999 among Lessee, Head
                           Lessor, Lessor, Participants and Agent.

                           (iv) A new definition of the term "Notice of Partial
                  Purchase Option Exercise", reading in its entirety as follows,
                  is added thereto in the appropriate alphabetical order:

                                    "Notice of Partial Purchase Option Exercise"
                           shall have, with respect to either Purchase
                           Agreement, the meaning given to that term in
                           Subparagraph 2.02(a) of such Purchase Agreement.

                           (v) The reference to "Paragraph 2.02" set forth in
                  the definition of the term "Notice of Term Purchase Option
                  Exercise" is changed to "Subparagraph 2.01(a)."

                           (vi) The date "August 30, 1999" set forth in the
                  definition of the term "Outside Completion Date" is changed to
                  "May 31, 2000."

                           (vii) New definitions of the terms "Partial Purchase
                  Date" and "Partial Purchase Option", reading in their entirety
                  as follows, are added thereto in the appropriate alphabetical
                  order:

                                    "Partial Purchase Date" shall have, with
                           respect to either Purchase Agreement, the meaning
                           given to that term in Subparagraph 2.02(a) of such
                           Purchase Agreement.

                                    "Partial Purchase Option" shall have, with
                           respect to either Purchase Agreement, the meaning
                           given to that term in Paragraph 2.02 of such Purchase
                           Agreement.

                           (viii) The reference to "Paragraph 3.01 of the
                  Facility 2 Construction Agency Agreement" in the definition of
                  the term "Plans and Specifications" is changed to "Paragraph
                  3.02 of the Facility 2 Construction Agency Agreement".



                                       4
<PAGE>   5

                           (ix) New definitions of the terms "Tract 4 Clean Room
                  Improvements" and "Tract 4 Clean Room Plans and
                  Specifications", reading in their entirety as follows, are
                  added thereto in the appropriate alphabetical order:

                                    "Tract 4 Clean Room Improvements" shall mean
                           additional improvements to be made to the "clean
                           room" located in the Improvements to the Tract 4 Land
                           and constituting part of the Facility 2 Property.

                                    "Tract 4 Clean Room Plans and
                           Specifications" shall have the meaning given to that
                           term in Subparagraph 2.01(d) of the Participation
                           Agreement.

         3. PRIOR FIRST AMENDMENT INEFFECTIVE. Certain of the parties to this
Amendment previously executed a First Amendment to Participation Agreement dated
as of November 9, 1998 (the "Prior First Amendment") pursuant to which Head
Lessor would have been authorized to sell on behalf of Lessee certain of the
Facility 1 Property and the Facility 2 Property. The sale of such property was
never effected, and, as a result, the conditions to the effectiveness of the
Prior First Amendment were never satisfied. The Prior First Amendment is
therefore declared null and void and of no force and effect.

         4. REPRESENTATIONS AND WARRANTIES. Lessee hereby represents and
warrants to Head Lessor, Lessor, Participants and Agent that the following are
true and correct on the date of this Amendment and that, after giving effect to
the amendments set forth in Paragraph 2 above, the following will be true and
correct on the Effective Date (as defined below):

                  (a) The representations and warranties of Lessee set forth in
         Paragraph 4.01 of the Participation Agreement and in the other
         Operative Documents are true and correct in all material respects as if
         made on such date (except for representations and warranties expressly
         made as of a specified date, which shall be true as of such date);

                  (b) No Default has occurred and is continuing; and

                  (c) All of the Operative Documents are in full force and
         effect.

(Without limiting the scope of the term "Operative Documents," Lessee expressly
acknowledges in making the representations and warranties set forth in this
Paragraph 4 that, on and after the date hereof, such term includes this
Amendment.)

         5. EFFECTIVE DATE. The amendments effected by Paragraph 2 above shall
become effective on June 4, 1999 (the "Effective Date"), subject to receipt by
Head Lessor, Lessor, Agent and the Participants prior to 9:00 A.M. (San
Francisco time) on the Effective Date of the following, each in form and
substance satisfactory to Head Lessor, Lessor, Agent, the Participants and their
respective counsel:



                                       5
<PAGE>   6

                  (a) This Amendment duly executed by Head Lessor, Lessor,
         Lessee, each Participant and Agent;

                  (b) A First Amendment to Facility 1 Purchase Agreement in the
         form of Exhibit A hereto, duly executed by Lessee and Lessor;

                  (c) A First Amendment to Facility 2 Purchase Agreement in the
         form of Exhibit B hereto, duly executed by Lessee and Lessor;

                  (d) A First Amendment to Facility 1 Head Lease Agreement in
         the form of Exhibit C hereto, duly executed by Head Lessor and Lessor;

                  (e) A First Amendment to Facility 2 Head Lease Agreement in
         the form of Exhibit D hereto, duly executed by Head Lessor and Lessor;

                  (f) An amendment to the Memorandum of Purchase Agreement for
         Facility 1, reflecting the amendments to the Facility 1 Purchase
         Agreement, duly executed by Lessee and Lessor and appropriately
         notarized for recording;

                  (g) An amendment to the Memorandum of Purchase Agreement for
         Facility 2, reflecting the amendments to the Facility 2 Purchase
         Agreement, duly executed by Lessee and Lessor and appropriately
         notarized for recording;

                  (h) An amendment to the Memorandum of Head Lease Agreement for
         Facility 1, reflecting the amendments to the Facility 1 Head Lease
         Agreement, duly executed by Head Lessor and Lessor and appropriately
         notarized for recording;

                  (i) An amendment to the Memorandum of Head Lease Agreement for
         Facility 2, reflecting the amendments to the Facility 2 Head Lease
         Agreement, duly executed by Head Lessor and Lessor and appropriately
         notarized for recording;

                  (j) Evidence that the Memoranda of Purchase Agreement and the
         Memoranda of Head Lease Agreement delivered pursuant to clauses 6(f),
         6(g), 6(h) and 6(i) above have been properly recorded in the Official
         Records of the County of Santa Clara, California;

                  (k) An Expiration Date Appraisal for the Facility 2 Property,
         dated as of a recent date prior to the Effective Date, that appraises
         the Facility 2 Property (including the Clean Room) at not less than the
         Total Facility 2 Commitment (as increased by this Amendment);

                  (l) A copy of the budget for the Clean Room which (i) includes
         provisions for all hard and soft costs of constructing the Clean Room
         (including, without limitation, all capitalized interest) and
         reasonable allowances for contingencies and (ii) budgets the aggregate
         cost of such construction at $20,000,000 or less; together with a
         certificate of



                                       6
<PAGE>   7

         the Chief Financial Officer of Lessee certifying that such budget is a
         reasonable budget that sets forth the likely maximum costs of
         constructing the Clean Room;

                  (m) Such endorsements as Lessor and Agent may reasonably
         request to each of (i) the ALTA extended coverage owner's interim title
         insurance binder for the Property insuring Lessor's fee simple title
         therein Property issued in connection with the closing of the
         Participation Agreement, (ii) the ALTA extended coverage lender's
         policy of title insurance for the Property insuring the validity and
         priority of the Lease Agreements in connection with the closing of the
         Participation Agreement, and (iii) the ALTA extended coverage lender's
         policy of title insurance for the Property insuring the validity and
         priority of the Lessor Deed of Trust issued in connection with the
         closing of the Participation Agreement;

                  (n) A Certificate of the Secretary of Lessee, dated the
         Effective Date, certifying that (i) the Articles of Incorporation and
         Bylaws of Lessee, in the form delivered to Agent on the Closing Date,
         are in full force and effect and have not been amended, supplemented,
         revoked or repealed since such date and (ii) that attached thereto are
         true and correct copies of resolutions duly adopted by the Board of
         Directors of Lessee and continuing in effect, which authorize the
         execution, delivery and performance by Lessee of this Amendment and the
         consummation of the transactions contemplated hereby;

                  (o) A favorable written opinion of Morrison & Foerster, LLP,
         counsel to Lessee, dated the Effective Date, addressed to Agent for the
         benefit of Lessor, Agent and Participants, covering such legal matters
         as Agent may reasonably request and otherwise in form and substance
         satisfactory to Agent;

                  (p) A certificate of the Chief Financial Officer of Lessee,
         addressed to Lessor and Agent and dated the Closing Date, certifying
         that:

                           (a) The representations and warranties set forth in
                  Paragraph 4.01 of the Participation Agreement and in the other
                  Operative Documents are true and correct in all material
                  respects as of such date (except for such representations and
                  warranties made as of a specified date, which shall be true as
                  of such date);

                           (b) No Default has occurred and is continuing as of
                  such date;

                           (c) All of the Operative Documents are in full force
                  and effect on such date;

                  (q) All fees and expenses payable to the Lessor Parties on or
         prior to the Effective Date;

                  (r) All fees and expenses of Lessor's and Agent's counsels
         through the Effective Date, to the extent set forth in statements of
         such counsels delivered to Lessee on or before the Effective Date; and



                                       7
<PAGE>   8

                  (s) Such other evidence as Head Lessor, Lessor, Agent or any
         Participant may reasonably request to establish the accuracy and
         completeness in all material respects of the representations and
         warranties and the compliance with the terms and conditions contained
         in this Amendment and the other Operative Documents.

Subject to receipt by Head Lessor, Lessor, Agent and the Participants of the
foregoing, (1) each Participant whose Proportionate Share under Facility 2 has
been increased by this Amendment shall pay to Agent, not later than 10:00 A.M.
(San Francisco time) on the Effective Date, such amount as Agent shall determine
is necessary to increase such Participant's Outstanding Participation Amount
under Facility 2 to such Participant's increased Proportionate Share of the
Outstanding Lease Amount under Facility 2 on the Effective Date and (2) promptly
upon its receipt of such funds, Agent shall pay to each Participant whose
Proportionate Share under Facility 2 has been decreased by this Amendment such
amount as Agent shall determine is necessary to decrease such Participant's
Outstanding Participation Amount under Facility 2 to such Participant's
decreased Proportionate Share of the Outstanding Lease Amount under Facility 2
on the Effective Date.

         6. EFFECT OF THIS AMENDMENT. On and after the Effective Date, each
reference in the Participation Agreement and the other Operative Documents to
the Participation Agreement shall mean the Participation Agreement as amended
hereby. Except as specifically amended above, (a) the Participation Agreement
and the other Operative Documents shall remain in full force and effect and are
hereby ratified and affirmed and (b) the execution, delivery and effectiveness
of this Amendment shall not, except as expressly provided herein, operate as a
waiver of any right, power, or remedy of Head Lessor, Lessor, Participants or
Agent, nor constitute a waiver of any provision of the Participation Agreement
or any other Operative Document.

         7. MISCELLANEOUS.

                  (a) Counterparts. This Amendment may be executed in any number
         of identical counterparts, any set of which signed by all the parties
         hereto shall be deemed to constitute a complete, executed original for
         all purposes.

                  (b) Headings. Headings in this Amendment are for convenience
         of reference only and are not part of the substance hereof.

                  (c) Governing Law. This Amendment shall be governed by and
         construed in accordance with the laws of the State of California
         without reference to conflicts of law rules.



                            [Signature pages follow]




                                       8
<PAGE>   9

         IN WITNESS WHEREOF, Lessee, Head Lessor, Lessor, Agent and the
Participants have caused this Amendment to be executed as of the day and year
first above written.

LESSEE:                                  NOVELLUS SYSTEMS, INC.

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


HEAD LESSOR:                             LEASE PLAN NORTH AMERICA, INC.


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


LESSOR:                                  ABN AMRO LEASING, INC.

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


AGENT:                                   ABN AMRO BANK N.V.

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


PARTICIPANTS:                            ABN AMRO BANK N.V.

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________




                                       9
<PAGE>   10

                                         KEYBANK NATIONAL ASSOCIATION

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE SUMITOMO BANK, LIMITED

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE INDUSTRIAL BANK OF JAPAN, LIMITED,
                                         SAN FRANCISCO AGENCY

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE BANK OF NOVA SCOTIA

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         UNION BANK OF CALIFORNIA, N.A.

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         COMERICA BANK-CALIFORNIA

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________



                                       10
<PAGE>   11

                                         FLEET NATIONAL BANK

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         BANQUE NATIONALE DE PARIS

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         CREDIT LYONNAIS LOS ANGELES BRANCH

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE FUJI BANK, LIMITED

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE LONG-TERM CREDIT BANK OF JAPAN,
                                         LIMITED, LOS ANGELES AGENCY

                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________



                                         THE MITSUBISHI TRUST AND BANKING
                                         CORPORATION, LOS ANGELES AGENCY


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________




                                       11
<PAGE>   12

                                         SOCIETE GENERALE


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         CALIFORNIA BANK & TRUST,
                                         formerly known as
                                         "The Sumitomo Bank of California"


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         THE SUMITOMO TRUST & BANKING CO., LTD.


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         SANWA BANK CALIFORNIA


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________


                                         ABN AMRO LEASING, INC.


                                         By:___________________________________
                                            Name:______________________________
                                            Title:_____________________________




                                       12
<PAGE>   13

                                  ATTACHMENT 1

         PART A(2) - TRANCHE PERCENTAGES AND PROPORTIONATE SHARES UNDER
                     FACILITY 2 PRIOR TO THE COMPLETION DATE




<TABLE>
<CAPTION>
                                       TRANCHE A             TRANCHE B              TRANCHE C           PROPORTIONATE
    PARTICIPANT                       PERCENTAGE             PERCENTAGE            PERCENTAGE                SHARE
----------------------------          ----------             ----------            ----------           -------------
<S>                                  <C>                     <C>                  <C>                  <C>
ABN AMRO Bank N.V                     12.20077785%           0.96357645%           0.00000000%          13.16435430%
KeyBank National Association           6.23634651%           0.49252570%           0.00000000%           6.72887221%
The Sumitomo Bank, Limited             6.23634651%           0.49252570%           0.00000000%           6.72887221%
The Industrial Bank of                 5.24517298%           0.41424614%            0.0000000%           5.65941912%
Japan, Limited, San
Francisco Agency
The Bank of Nova Scotia                8.72564589%           0.68912220%            0.0000000%           9.41476809%
Union Bank of California,              4.24071563%           0.33491747%            0.0000000%           4.57563310%
N.A
Comerica Bank-California               3.99126177%           0.31521645%            0.0000000%           4.30647822%
Fleet National Bank                    5.99459342%           0.47343285%            0.0000000%           6.46802627%
Banque Nationale de Paris              6.98470810%           0.55162878%            0.0000000%           7.53633688%
Credit Lyonnais Los Angeles            4.54459579%           0.35891691%            0.0000000%           4.90351270%
Branch
The Fuji Bank, Limited                 7.14827011%           0.56454636%            0.0000000%           7.71281647%
The Long-Term Credit Bank of           3.49235405%           0.27581439%            0.0000000%           3.76816844%
Japan, Ltd., Los Angeles
Agency
The Mitsubishi Trust and               3.49235405%           0.27581439%            0.0000000%           3.76816844%
Banking Corporation, Los
Angeles Agency
Societe Generale                       3.49235405%           0.27581439%            0.0000000%           3.76816844%
California Bank & Trust,               3.49235405%           0.27581439%            0.0000000%           3.76816844%
formerly known as "The
Sumitomo Bank of California"
Sanwa Bank California                  4.38214926%           0.34608743%            0.0000000%           4.72823669%
ABN AMRO Leasing, Inc
                                                0%                    0%           3.00000000%           3.00000000%
TOTAL                                 89.90000000%           7.10000000%           3.00000000%         100.00000000%
</TABLE>




                                     [1]-1
<PAGE>   14

     PART A(3) - TRANCHE PERCENTAGES AND PROPORTIONATE SHARES UNDER FACILITY
                       2 ON AND AFTER THE COMPLETION DATE

<TABLE>
<CAPTION>
                                       TRANCHE A             TRANCHE B              TRANCHE C           PROPORTIONATE
    PARTICIPANT                       PERCENTAGE             PERCENTAGE            PERCENTAGE               SHARE
----------------------------          ----------             ----------            ----------           -------------
<S>                                  <C>                     <C>                  <C>                  <C>
ABN AMRO Bank N.V                     12.62149432%           0.54285997%           0.00000000%          13.16435430%
KeyBank National Association           6.45139294%           0.27747927%           0.00000000%           6.72887221%
The Sumitomo Bank, Limited             6.45139294%           0.27747927%           0.00000000%           6.72887221%
The Industrial Bank of                 5.42604102%           0.23337811%           0.00000000%           5.65941912%
Japan, Limited, San
Francisco Agency
The Bank of Nova Scotia                9.02653023%           0.38823786%           0.00000000%           9.41476809%
Union Bank of California,              4.38694720%           0.18868590%           0.00000000%           4.57563310%
N.A
Comerica Bank-California               4.12889149%           0.17758673%           0.00000000%           4.30647822%
Fleet National Bank                    6.20130354%           0.26672273%           0.00000000%           6.46802627%
Banque Nationale de Paris              7.22556010%           0.31077678%           0.00000000%           7.53633688%
Credit Lyonnais Los Angeles            4.70130599%           0.20220671%           0.00000000%           4.90351270%
Branch
The Fuji Bank, Limited                 7.39476218%           0.31805429%           0.00000000%           7.71281647%
The Long-Term Credit Bank of           3.61278005%           0.15538839%           0.00000000%           3.76816844%
Japan, Ltd., Los Angeles
Agency
The Mitsubishi Trust and               3.61278005%           0.15538839%           0.00000000%           3.76816844%
Banking Corporation, Los
Angeles Agency
Societe Generale                       3.61278005%           0.15538839%           0.00000000%           3.76816844%
California Bank & Trust,               3.61278005%           0.15538839%           0.00000000%           3.76816844%
formerly known as "The
Sumitomo Bank of California"
Sanwa Bank California                  4.53325786%           0.19497883%           0.00000000%           4.72823669%
ABN AMRO Leasing, Inc.
                                                0%                    0%           3.00000000%           3.00000000%
TOTAL                                 93.00000000%           4.00000000%           3.00000000%         100.00000000%
</TABLE>



                                     [1]-2
<PAGE>   15

                                    EXHIBIT A

                FIRST AMENDMENT TO FACILITY 1 PURCHASE AGREEMENT

                                 See Attachment.













                                      A-1
<PAGE>   16


                                    EXHIBIT B

                FIRST AMENDMENT TO FACILITY 2 PURCHASE AGREEMENT

                                 See Attachment.













                                      B-1
<PAGE>   17

                                    EXHIBIT C

               FIRST AMENDMENT TO FACILITY 1 HEAD LEASE AGREEMENT

                                 See Attachment.












                                      C-1
<PAGE>   18
                                    EXHIBIT D

               FIRST AMENDMENT TO FACILITY 2 HEAD LEASE AGREEMENT

                                 See Attachment.









                                      D-1