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                                                                   EXHIBIT 10.26

                      FOURTH AMENDMENT TO CREDIT AGREEMENT
                      ------------------------------------


     THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (the "Amendment"), dated as of
                                                     ---------
September 18, 1998, is entered into between MELLON BANK, N.A. (the "Bank"), with
                                                                    ----
a place of business at 400 South Hope Street, 5th Floor, Los Angeles, California
90071, and KEYSTONE AUTOMOTIVE INDUSTRIES, INC., a California corporation
("Borrower"), with its chief executive office located at 700 East Bonita Avenue,
----------
Pomona, California 91767.

                                    RECITAL
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     A.   Borrower and the Bank have previously entered into that certain Credit
Agreement dated as of March 25, 1997, as amended by that certain First Amendment
to Credit Agreement dated as of August 25, 1997, that certain Second Amendment
to Credit Agreement dated as of March 17, 1998 and that certain Third Amendment
to Credit Agreement dated as of June 29, 1998 (collectively, the "Credit
                                                                  ------
Agreement"), pursuant to which the Bank has made certain loans and other
---------
financial accommodations available to Borrower.  Terms used herein without
definition shall have the meanings ascribed to them in the Credit Agreement.

     B.   Borrower has requested that the Bank amend the Credit Agreement to (a)
amend the definition of "Guarantors", (b) extend the Maturity Date of the Credit
Agreement and (c) correct a section reference in the definition of "Portion".

     C.   The Bank is willing to further amend the Credit Agreement under the
terms and conditions set forth in this Amendment. Borrower is entering into this
Amendment with the understanding and agreement that, except as specifically
provided herein, none of the Bank's rights or remedies as set forth in the
Credit Agreement is being waived or modified by the terms of this Amendment.

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants
herein contained, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:

     1.   Amendments to Credit Agreement.
          ------------------------------

          (a) The definition of "Guarantors" set forth in Section 1.1 of the
     Credit Agreement is hereby amended in its entirety as follows:

              "`Guarantors': Any material subsidiary of the Borrower, as
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          determined by Bank, organized under the laws of the United States of
          America or any political subdivision thereof. Without limiting the
          generality of the foregoing, `Guarantors' shall include North Star
          Plating Company, a Minnesota corporation, Inteuro Parts Distributors,
          Inc. a Florida corporation, and Car Body Concepts, Inc., a Florida
          corporation, Republic Automotive Parts, Inc., a Delaware corporation,
          and Fenders & More, Inc., a Tennessee corporation."
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          (b) The definition of "Maturity Date" as set forth in Section 1.1 of
     the Credit Agreement is hereby amended in its entirety as follows:

              "`Maturity Date':  September 17, 1999."
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          (c) The definition of "Portion" as set forth in Section 1.1 of the
     Credit Agreement is hereby amended in its entirety as follows:

              "`Portion':  `Prime Rate Portion' shall mean at any time the part,
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          including the whole, of the unpaid principal amount of the Note
          bearing interest at such time under the Prime Rate Option, in
          accordance with Section 2.4 (b) hereof, or in accordance with Section
          2.4 (f) hereof.  `Libor Rate Portion' shall mean at any time, the
                            ------------------
          part, including the whole, of the unpaid principal amount of the Note
          bearing interest at such time under the Libor Rate Option, in
          accordance with Section 2.4 (b) hereof."

     2.   Effectiveness of this Amendment.  Each of the following is a condition
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precedent to the effectiveness of this Amendment and to the Bank's obligation to
extend any credit to Borrower as provided for by this Amendment:

          (a) Amendment,  The Bank shall have received, in form and substance
              ---------
     satisfactory to the Bank, this Amendment fully executed in a sufficient
     number of counterparts for distribution to the Bank and Borrower.

          (b) Authorizations.  The Bank shall have received evidence, in form
              --------------
     and substance satisfactory to the Bank, that the execution, delivery and
     performance by Borrower and each Guarantor and any instrument or agreement
     required under this Amendment have been duly authorized.

          (c) Representations and Warranties.  The Representations and
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     Warranties set forth in the Credit Agreement must be true and correct as of
     the date of this Amendment as if made as of such date.

          (d) No Event of Default.  As of the date hereof and after giving
              -------------------
     effect to the Republic Acquisition, no Event of Default, or event which
     with notice or passage of time or both would constitute an Event of
     Default, exists or has occurred and is continuing.

          (e) Other Required Documentation. All other documents and legal
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     matters in connection with the transactions contemplated by this Agreement
     shall have been delivered or executed or recorded and shall be in form and
     substance satisfactory to the Bank.

     3.   Representations and Warranties.  The Borrower represents and warrants
          ------------------------------
as follows:

          (a) Authority.  Borrower has the requisite corporate power and
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     authority to execute and deliver this Amendment, and to perform its
     obligations hereunder and under the Loan Documents (as amended or modified
     hereby).  The execution, delivery and

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     performance by the Borrower of this Amendment and each Loan Document (as
     amended or modified hereby) have been duly approved by all necessary
     corporate action of Borrower and no other corporate proceedings on the part
     of Borrower are necessary to consummate such transactions.

          (b) Enforceability.  This Amendment has been duly executed and
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     delivered by Borrower.  This Amendment and each Loan Document (as amended
     or modified hereby) is the legal, valid and binding obligation of Borrower,
     enforceable against Borrower in accordance with its terms, and is in full
     force and effect.

          (c) Representations and Warranties.  The representations and
              ------------------------------
     warranties contained in each Loan Document (other than any such
     representations or warranties that, by their terms, are specifically made
     as of a date other than the date hereof) are correct on and as of the date
     hereof as though made on and as of the date hereof.

          (d) No Default.  As of the date hereof and after giving effect to the
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     Republic Acquisition, no event has occurred and is continuing that
     constitutes, or would with notice or passage of time or both would
     constitute, an Event of Default.

     4.   Choice of Law.  The validity of this Amendment, its construction,
          -------------
interpretation and enforcement, the rights of the parties hereunder, shall be
determined under, governed by, and construed in accordance with the internal
laws of the State of California governing contracts only to be performed in that
State.

     5.   Counterparts.  This Amendment may be executed in any number of
          ------------
counterparts and by different parties and separate counterparts, each of which
when so executed and delivered, shall be deemed an original, and all of which,
when taken together, shall constitute one and the same instrument.  Delivery of
an executed counterpart of a signature page to this Amendment by telefacsimile
shall be effective as delivery of a manually executed counterpart of this
Amendment.

     6.   Due Execution.  The execution, delivery and performance of this
          -------------
Amendment are within the power of Borrower, have been duly authorized by all
necessary corporate action, have received all necessary governmental approval,
if any, and do not contravene any law or any contractual restrictions binding on
Borrower.

     7.   Reference to and Effect on the Loan Documents.
          ---------------------------------------------

          (a) Upon and after the effectiveness of this Amendment, each reference
     in the Credit Agreement to "this Agreement", "hereunder", "hereof" or words
     of like import referring to the Credit Agreement, and each reference in the
     other Loan Documents to "the Credit Agreement", "thereof" or words of like
     import referring to the Credit Agreement, shall mean and be a reference to
     the Credit Agreement as modified and amended hereby.

          (b) Except as specifically amended above, the Credit Agreement and all
     other Loan Documents, are and shall continue to be in full force and effect
     and are hereby in all

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     respects ratified and confirmed and shall constitute the legal, valid,
     binding and enforceable obligations of Borrower to the Bank.

          (c) 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 any the Bank or the Agent under any of the Loan
     Documents, nor constitute a waiver of any provision of any of the Loan
     Documents.

          (d) To the extent that any terms and conditions in any of the Loan
     Documents shall contradict or be in conflict with any terms or conditions
     of the Credit Agreement, after giving effect to this Amendment, such terms
     and conditions are hereby deemed modified or amended accordingly to reflect
     the terms and conditions of the Credit Agreement as modified or amended
     hereby.

     8.   Ratification.  Borrower hereby restates, ratifies and reaffirms each
          ------------
and every term and condition set forth in the Credit Agreement, as amended
hereby, and the Loan Documents effective as of the date hereof.

     9.   Estoppel.  To induce the Bank to enter into this Amendment and to
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continue to make advances to Borrower under the Credit Agreement, Borrower
hereby acknowledges and agrees that, after giving effect to this Amendment, as
of the date hereof, there exists no Event of Default and no right of offset,
defense, counterclaim or objection in favor of Borrower as against the Bank with
respect to the Obligations.

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     IN WITNESS WHEREOF, the parties have entered into this Amendment as of the
date first above written.

                                   KEYSTONE AUTOMOTIVE INDUSTRIES, INC.,
                                   a California corporation


                                   By: /s/ John M. Palumbo
                                      ------------------------------
                                   Name: John M. Palumbo
                                   Title: Chief Financial Officer



                                   MELLON BANK, N.A.,
                                   a national association


                                   By: /s/ Kevin D. Kelly
                                      ------------------------------
                                   Name: Kevin D. Kelly
                                   Title: Vice President

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