<PAGE>
                                                                EXHIBIT 10.10(f)



                               FIFTH AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT

                  This FIFTH AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT (this
"Amendment") is entered into as of September 30, 2002, and amends that certain
Receivables Purchase Agreement, dated as of October 6, 2000, amended as of July
1, 2001, further amended as of October 3, 2001, further amended as of April 25,
2002, and further amended as of June 28, 2002 (such agreement, as so amended,
the "Existing Agreement"), by and among Plexus ABS, Inc., a Nevada corporation
("Seller"), Plexus Corp., a Wisconsin corporation ("Plexus"), as initial
Servicer (the Servicer together with Seller, the "Seller Parties" and each a
"Seller Party"), the Financial Institutions party thereto from time to time,
Preferred Receivables Funding Corporation ("PREFCO") and Bank One, NA (Main
Office Chicago), as agent for the Purchasers thereunder and any successor agent
thereunder (together with its successors and assigns thereunder, the "Agent").
Capitalized terms used herein and not otherwise defined shall have the
respective meanings set forth in the Existing Agreement.

                                R E C I T A L S:
                                - - - - - - - -

                  WHEREAS, the Seller Parties, the Financial Institutions,
PREFCO and the Agent are parties to the Existing Agreement; and

                  WHEREAS, the Seller Parties, the Financial Institutions,
PREFCO and the Agent desire to amend certain provisions of the Existing
Agreement as more fully described herein.

                  NOW, THEREFORE, in consideration of the premises, and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto hereby agree as follows:

                  Section 1. Amendments. Subject to the terms and conditions set
forth herein, the Existing Agreement is hereby amended by:

                           (a) replacing the definition of "Aggregate Reserves"
set forth in Exhibit I of the Existing Agreement in its entirety with the
following:



<PAGE>




                  "Aggregate Reserves" means, on any date of determination, an
         amount equal to thirty-one percent (31%) of the Net Receivables Balance
         on such date.

                           (b) replacing the definition of "Concentration Limit"
set forth in Exhibit I of the Existing Agreement in its entirety with the
following:

                  "Concentration Limit" means, at any time, (a) for any Obligor
         other than as described in part (b) of this definition or cancelled
         pursuant to this definition, 8.33% of the Net Receivables Balance at
         such time, (b)(i) for Motorola, Inc., 9% of the Net Receivables Balance
         at such time, (ii) for Arrowpoint Communications, Inc. and Cisco
         Systems, Inc., collectively and not individually, 12.50% of the Net
         Receivables Balance at such time, (iii) for General Electric Company,
         25% of the Net Receivables Balance at such time and (iv) for Siemens
         AG, 12.50% of the Net Receivables Balance at such time (each of the
         foregoing, a "Special Obligor Concentration Limit") or (c) for any
         Obligor, such other amount for such Obligor designated by the Agent
         (each such other amount, a "Special Concentration Limit"); provided,
         that in the case of an Obligor and any Affiliate of such Obligor, the
         Concentration Limit shall be calculated as if such Obligor and such
         Affiliate are one Obligor; and provided, further, that Company or the
         Required Financial Institutions may, upon not less than three Business
         Days' notice to Seller, cancel any Special Obligor Concentration Limit
         or Special Concentration Limit.

                           (c) replacing the definition of "Liquidity
Termination Date" set forth in Exhibit I of the Existing Agreement in its
entirety with the following:

                  "Liquidity Termination Date" means September 26, 2003.

                  Section 2. Conditions to Effectiveness of Amendments. The
amendments set forth in Section 1 of this Amendment shall become effective as of
the date hereof, upon the satisfaction of the following conditions precedent:

                           (a) Amendment. This Amendment shall have been duly
executed and delivered by each of the parties hereto.




                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT
                                       2

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                           (b) Officer's Certificate. The Agent shall have
received a certificate of an authorized officer of each of the Servicer and
Seller in the forms set forth as Exhibits A and B, respectively, certifying as
to matters set forth in Sections 3(a) and (b) of this Amendment.

                  Section 3. Representations and Warranties. Each of Seller and
the Servicer represents and warrants to the Financial Institutions, PREFCO and
the Agent that, as of the date hereof, both before and after giving effect to
the amendments set forth in Section 1 of this Amendment:

                           (a) no Amortization Event or Potential Amortization
Event has occurred and is continuing; and

                           (b) all of the representations and warranties
contained in the Existing Agreement and in the other Transaction Documents are
true and correct.

                  Section 4.  Miscellaneous.

                           (a) Effect; Ratification. The amendments set forth
herein are effective solely for the purposes set forth herein and shall be
limited precisely as written, and shall not be deemed to (i) be a consent to any
amendment, waiver or modification of any other term or condition of the Existing
Agreement or of any other instrument or agreement referred to therein; or (ii)
prejudice any right or remedy which the Financial Institutions, PREFCO or the
Agent may now have or may have in the future under or in connection with the
Existing Agreement, as amended hereby, or any other instrument or agreement
referred to therein. Each reference in the Existing Agreement to "this
Agreement," "herein," "hereof" and words of like import and each reference in
the other Transaction Documents to the "Receivables Purchase Agreement," the
"Purchase Agreement" or the Existing Agreement shall mean the Existing Agreement
as amended hereby. This Amendment shall be construed in connection with and as
part of the Existing Agreement and all terms, conditions, representations,
warranties, covenants and agreements set forth in the Existing Agreement and
each other instrument or agreement referred to therein, except as herein
amended, are hereby ratified and confirmed and shall remain in full force and
effect.

                           (b) Transaction Documents. This Amendment is a
Transaction Document executed pursuant to the Existing Agreement and shall be
construed, administered and applied in accordance with the terms and provisions
thereof.


                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT
                                       3


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                           (c) Costs, Fees and Expenses. Seller agrees to
reimburse the Agent and each Purchaser on demand for all costs, fees and
expenses (including the reasonable fees and expenses of counsel to the Agent and
the Purchasers) incurred in connection with the preparation, execution and
delivery of this Amendment.

                           (d) Counterparts. This Amendment may be executed in
any number of counterparts, each such counterpart constituting an original and
all of which when taken together shall constitute one and the same instrument.

                           (e) Severability. Any provision contained in this
Amendment which is held to be inoperative, unenforceable or invalid in any
jurisdiction shall, as to that jurisdiction, be inoperative, unenforceable or
invalid without affecting the remaining provisions of this Amendment in that
jurisdiction or the operation, enforceability or validity of such provision in
any other jurisdiction.

                           (f) GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED
BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
ILLINOIS.



                            (Signature Page Follows)


                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT
                                       4

<PAGE>




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


                               PLEXUS ABS, INC.


                               By:      /s/
                                  ----------------------------------------------
                               Name:
                                    --------------------------------------------
                               Title:
                                     -------------------------------------------


                               PLEXUS CORP.


                               By:      /s/
                                  ----------------------------------------------
                               Name:
                                    --------------------------------------------
                               Title:
                                     -------------------------------------------


                               PREFERRED RECEIVABLES FUNDING CORPORATION


                               By:      /s/
                                  ----------------------------------------------
                                        Authorized Signer


                               BANK ONE, NA (MAIN OFFICE CHICAGO),
                               as a Financial Institution and as Agent


                               By:      /s/
                                  ----------------------------------------------
                               Name:
                                    --------------------------------------------
                               Title:
                                     -------------------------------------------




                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT
<PAGE>


                                                                       EXHIBIT A

                              OFFICER'S CERTIFICATE

                  I, ______________, am the _______________ of Plexus Corp. (the
"Servicer"). I execute and deliver this Officer's Certificate, dated as of
September 30, 2002, on behalf of the Servicer pursuant to Section 2(b) of the
Fifth Amendment to Receivables Purchase Agreement (the "Amendment"), dated as of
the date hereof, among the Seller Parties, the Financial Institutions, PREFCO
and the Agent (each as defined therein), amending certain provisions of that
certain Receivables Purchase Agreement, dated as of October 6, 2000, amended as
of July 1, 2001, further amended as of October 3, 2001, further amended as of
April 25, 2002, and further amended as of June 28, 2002 (such agreement, as so
amended, the "Existing Agreement"), among the Seller Parties, the Financial
Institutions, PREFCO and the Agent. Capitalized terms used herein and not
defined herein shall have the meanings set forth for such terms in the Existing
Agreement.

                  I hereby certify, on behalf of the Servicer, that to the best
of my knowledge after due inquiry, as of the date hereof, both before and after
giving effect to the amendments set forth in Section 1 of the Amendment, (a) no
Amortization Event or Potential Amortization Event has occurred and is
continuing and (b) the representations and warranties of Seller and the Servicer
contained in the Existing Agreement and in the other Transaction Documents are
true and correct as of the date hereof.





                                            ----------------------------------
                                            Name:
                                            Title:





                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT
<PAGE>



                                                                       EXHIBIT B

                              OFFICER'S CERTIFICATE

                  I, ______________, am the _______________ of Plexus ABS, Inc.
("Seller"). I execute and deliver this Officer's Certificate, dated as of
September 30, 2002, on behalf of Seller pursuant to Section 2(b) of the Fifth
Amendment to Receivables Purchase Agreement (the "Amendment"), dated as of the
date hereof, among the Seller Parties, the Financial Institutions, PREFCO and
the Agent (each as defined therein), amending certain provisions of that certain
Receivables Purchase Agreement, dated as of October 6, 2000, amended as of July
1, 2001, further amended as of October 3, 2001, further amended as of April 25,
2002, and further amended as of June 28, 2002 (such agreement, as so amended,
the "Existing Agreement"), among the Seller Parties, the Financial Institutions,
PREFCO and the Agent. Capitalized terms used herein and not defined herein shall
have the meanings set forth for such terms in the Existing Agreement.

                  I hereby certify, on behalf of Seller, that to the best of my
knowledge after due inquiry, as of the date hereof, both before and after giving
effect to the amendments set forth in Section 1 of the Amendment, (a) no
Amortization Event or Potential Amortization Event has occurred and is
continuing and (b) the representations and warranties of Seller contained in the
Existing Agreement and in the other Transaction Documents are true and correct
as of the date hereof.





                                            ----------------------------------
                                            Name:
                                            Title:





                                                              FIFTH AMENDMENT TO
                                                  RECEIVABLES PURCHASE AGREEMENT