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                                                                     EXHIBIT 4.2

                  AGREEMENT OF SUBSTITUTION AND FIRST AMENDMENT
                           TO THE AMENDED AND RESTATED
                          SHAREHOLDERS RIGHTS AGREEMENT


         THIS AGREEMENT (the "First Amendment") is made as of this 5th day of
December, 2002, by and between Plexus Corp. (the "Company") and American Stock
Transfer & Trust Company, a New York banking corporation ("AST").

         WHEREAS, the Company entered into a Shareholder Rights Agreement as of
August 13, 1998, as amended and restated on November 14, 2000 (the "Rights
Agreement"), with Firstar Bank, N.A. (f/k/a Firstar Trust Co.) (the "Predecessor
Rights Agent");

         WHEREAS, the Company and the Rights Agent, if directed by the Company,
may, from time to time, supplement or amend the Rights Agreement pursuant to the
provisions of Section 5.9 of the Rights Agreement;

         WHEREAS, no "Flip in" or "Flip over", Share Acquisition Date or
Distribution Date (as defined in the Rights Agreement) has occurred;

         WHEREAS, the Board of Directors of the Company has desires to remove
the Predecessor Rights Agent and substitute AST as Rights Agent pursuant to
Section 4.5 of the Rights Agreement;

         WHEREAS, the Company has given the Predecessor Rights Agent notice of
removal of the Predecessor Rights Agent and the substitution of AST as the new
Rights Agent under the Rights Agreement;

         WHEREAS, this Amendment complies with the terms of the Rights
Agreement;

         WHEREAS, all acts and things necessary to make this Amendment to the
Rights Agreement a valid, legal, binding instrument of the Company and the
Rights Agreement have been duly done, performed and fulfilled in the execution
and delivery hereof.

         NOW, THEREFORE, the Company and AST hereby agree:

         1. The Company hereby appoints AST as Rights Agent pursuant to Section
4.5 of the Rights Agreement, to serve in that capacity for the consideration and
subject to all the terms and conditions of the Rights Agreement.

         2. AST hereby accepts the appointment as Rights Agent pursuant to
Section 4.5 of the Rights Agreement and agrees to serve in that capacity for the
consideration and subject to all the terms and conditions of the Rights
Agreement.

         3. From and after the date of this Agreement, each and every reference
in the Rights Agreement to the "Rights Agent" shall be deemed to be a reference
to AST.



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         4. The parties agree to amend Section 4.5 of the Rights Agreement to
read as follows:

            4.5 Resignation or Removal of the Rights Agent. The Rights Agent or
         any successor Rights Agent may resign and be discharged from its
         obligations and duties under this Agreement upon 30 days' prior notice
         to the Company and to each transfer agent for the Preferred Shares and
         for the Common Stock of the Company, sent by registered or certified
         mail, postage prepaid, and to each registered holder of the Rights
         Certificates, sent by first-class mail, postage prepaid. The Company
         may remove the Rights Agent or any successor Rights Agent upon 30 days'
         prior notice to the Rights Agent or successor Rights Agent, as the case
         may be, and to each transfer agent for the Preferred Shares and for the
         Common Stock of the Company, sent by registered or certified mail,
         postage prepaid, and to each registered holder of the Rights
         Certificates, sent by first class mail, postage prepaid. If the Rights
         Agent or any successor Rights Agent shall resign or be removed or shall
         otherwise become incapable of acting, the Company shall appoint a
         successor Rights Agent. If the Company shall fail to make such
         appointment within 30 days after giving notice of such removal or after
         receiving notice of such resignation or incapacity, either from the
         resigning or incapacitated Rights Agent or from the registered holder
         of any Rights Certificate (who shall, with such notice, submit its
         Rights Certificate for inspection by the Company), then the incumbent
         Rights Agent or the registered holder of any Rights Certificate may
         apply to any court of competent jurisdiction for the appointment of a
         successor Rights Agent. Any successor Rights Agent, whether appointed
         by the Company or by such a court, shall be a corporation or banking
         institution organized and doing business under the laws of the United
         States of America or the State of Wisconsin or State of New York (or of
         any other state so long as such corporation is authorized to do
         business as a banking institution in the State of Wisconsin), be in
         good standing under the laws of the jurisdiction of its incorporation,
         have an office in the State of Wisconsin, be authorized under such laws
         to exercise corporate trust or stock transfer powers, be subject to
         supervision or examination by federal or state authority and have at
         the time of its appointment as Rights Agent a combined capital and
         surplus of at least $10,000,000. After its appointment, the successor
         Rights Agent shall be vested with the same rights, powers, obligations,
         duties and immunities as if it had been originally named as Rights
         Agent without further act or deed; but the predecessor Rights Agent
         shall deliver and transfer to the successor Rights Agent any property
         at the time held by it hereunder, and execute and deliver any further
         assurance, conveyance, act or deed necessary for the purpose. Not later
         than the effective date of any such appointment, the Company shall file
         notice thereof in writing with the predecessor Rights Agent and each
         transfer agent for the Preferred Shares and for the Common Stock of the
         Company, and mail notice thereof to the registered holders of the
         Rights Certificates. Failure to give any notice provided for in this
         Section, however, or any defect therein, shall not affect the legality
         or validity of the resignation or removal of the Rights Agent or any
         successor Rights Agent or the appointment of any successor thereto.


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         5. Pursuant to Section 5.8 of the Rights Agreement, the address for
notices to the Rights Agent shall be as follows:

                        American Stock & Transfer Trust Company
                        59 Maiden Lane
                        New York NY  10038
                        Attn: Corporate Trust Department

         6. This Agreement may be executed in two or more counterparts (by fax
or otherwise) and each of such counterparts shall for all purposes be deemed an
original and all such counterparts together shall constitute one and the same
instrument.

         7. Capitalized terms not defined herein shall, unless the context
otherwise requires, have the meanings assigned to them by such terms in the
Rights Agreement.

         8. If any term, provision, covenant or restriction of this First
Amendment is held by a court of competent jurisdiction or other authority to be
invalid, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions of this First Amendment shall remain in full force
and effect and shall in no way be affected, impaired or invalidated.

         9. This Agreement shall be deemed to be a contract made under the
internal laws of the State of Wisconsin and for all purposes shall be governed
by and construed in accordance with the laws of Wisconsin applicable to
contracts made and to be performed entirely within Wisconsin.

         10. Except to the extent amended hereby, the terms and provisions of
the Rights Agreement are hereby ratified and confirmed.



                           [SIGNATURE PAGE TO FOLLOW]


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         IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed and attested all as of the day and year first written above.


                                       PLEXUS CORP.


                                       By: /s/ Joseph D. Kaufman
                                       Its: Senior Vice President and Secretary



                                       AMERICAN STOCK & TRANSFER COMPANY


                                       By: /s/ Herbert J. Lemmer
                                       Its: Vice President



                                       US BANK, N.A. (f/k/a FIRSTAR BANK,
                                       NA and FIRSTAR TRUST CO.)


                                       By: /s/ John R. Horvath
                                       Its: Vice President



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