Document:

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                                                                 EXHIBIT 10.6(b)

                                  PLEXUS CORP.
                 FIRST AMENDMENT AND WAIVER TO CREDIT AGREEMENT

         This First Amendment and Waiver to Credit Agreement (herein, the
"Amendment") is entered into as of October 31, 2003, by and among Plexus Corp.,
a Wisconsin corporation (the "Borrower"), the Subsidiaries listed on the
signature pages hereof, as Guarantors, the several financial institutions listed
on the signature pages hereof, as Lenders, and Harris Trust and Savings Bank, as
Administrative Agent for the Lenders.

                             PRELIMINARY STATEMENTS

          A. The Borrower, the Guarantors, the Lenders and the Administrative
Agent are parties to a Credit Agreement dated as of October 22, 2003 (the
"Credit Agreement"). All capitalized terms used herein without definition shall
have the same meanings herein as such terms have in the Credit Agreement.

         B. The Borrower has requested that the Lenders (i) amend Section
8.21(b) of the Credit Agreement so as to allow cash held by Wholly-owned
Subsidiaries of the Borrower to count against the required amount thereunder and
(ii) waive for a certain period following the date hereof any Default or Event
of Default which would otherwise be caused by the existence of certain Liens not
otherwise permitted pursuant to the terms of Section 8.8 of the Credit Agreement
on the assets of the Borrower and its Subsidiaries.

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

SECTION 1. WAIVER.

         By signing below, subject to the satisfaction of the conditions
precedent set forth below, the Lenders hereby waive during the period from and
including the Closing Date through but excluding December 15, 2003 any violation
of Section 8.8 of Credit Agreement which could or would otherwise be caused by
the existence of the Liens described in a certain memorandum from Chapman and
Cutler dated on or about the date hereof (the "Post-Closing Liens"), copies of
which memorandum have been distributed to the Lenders prior to the date hereof,
provided that the Borrower agrees that (i) the waiver set forth in this Section
1 shall expire on December 15, 2003, and (ii) it shall use commercially
reasonable efforts to have the Post-Closing Liens released prior to December 15,
2003 or, alternatively, to cause the secured parties holding such Liens to enter
into intercreditor agreements with the Administrative Agent relating to such
Liens prior to December 15, 2003, which intercreditor agreements shall be in
form and substance acceptable to the Required Lenders.

SECTION 2. AMENDMENT.

         Subject to the satisfaction of the conditions precedent set forth in
Section 3 below, Section 8.21(b) of the Credit Agreement shall be and hereby is
amended by deleting the words
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"The Borrower shall . . . " and replacing them with the words "The Borrower and
its Wholly-owned Subsidiaries shall . . .".

SECTION 3. CONDITION PRECEDENT.

         The effectiveness of this Amendment is subject to the satisfaction of
the following condition precedent:

                  3.1. The Borrower, the other Guarantors and the Required
         Lenders shall have executed and delivered this Amendment.

SECTION 4. REPRESENTATIONS.

         In order to induce the Lenders to execute and deliver this Amendment,
the Borrower hereby represents to the Lenders that as of the date hereof the
representations and warranties set forth in Section 6 of the Credit Agreement as
amended hereby are and shall be and remain true and correct (except, with
respect to the representation set forth in Section 6.10, to the extent that any
Default or Event of Default which would otherwise be caused by the existence of
Liens not permitted by Section 8.8 of the Credit Agreement is specifically
waived hereby) and that the Borrower is in compliance with the terms and
conditions of the Credit Agreement and no Default or Event of Default has
occurred and is continuing under the Credit Agreement or shall result after
giving effect to this Amendment (other than any such Default or Event of Default
as is specifically waived hereby).

SECTION 5. MISCELLANEOUS.

        5.1. The Borrower and the other Guarantors (collectively, the "Credit
Parties") have heretofore executed and delivered to the Lenders the Collateral
Documents. The Credit Parties hereby acknowledge and agrees that the Liens
created and provided for by the Collateral Documents continue to secure, among
other things, the Obligations arising under the Credit Agreement as amended
hereby; and the Collateral Documents and the rights and remedies of the Lenders
thereunder, the obligations of the Borrower, and the other Guarantors
thereunder, and the Liens created and provided for thereunder, remain in full
force and effect and shall not be affected, impaired or discharged hereby.
Nothing herein contained shall in any manner affect or impair the priority of
the liens and security interests created and provided for by the Collateral
Documents as to the indebtedness which would be secured thereby prior to giving
effect to this Amendment.

        5.2. Except as specifically amended herein, the Credit Agreement shall
continue in full force and effect in accordance with its original terms.
Reference to this specific Amendment need not be made in the Credit Agreement,
the Notes, or any other instrument or document executed in connection therewith,
or in any certificate, letter or communication issued or made pursuant to or
with respect to the Credit Agreement, any reference in any of such items to the
Credit Agreement being sufficient to refer to the Credit Agreement as amended
hereby.

                                      -2-
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        5.3. The Borrower agrees to pay on demand all reasonable third party
costs and expenses incurred by the Administrative Agent in connection with the
negotiation, preparation, execution and delivery of this Amendment, including
the reasonable fees and expenses of counsel for the Administrative Agent.

        5.4. This Amendment may be executed in any number of counterparts, and
by the different parties on different counterpart signature pages, all of which
taken together shall constitute one and the same agreement. Any of the parties
hereto may execute this Amendment by signing any such counterpart and each of
such counterparts shall for all purposes be deemed to be an original. This
Amendment shall be governed by the internal laws of the State of Illinois.

                           [SIGNATURE PAGE TO FOLLOW]

                                      -3-
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         This First Amendment and Waiver to Credit Agreement is entered into as
of this 31st day of October, 2003.

                                         BORROWER

                                         PLEXUS CORP.

                                         By    /s/ George W.F. Setton
                                           ----------------------------------
                                            Name  George W.F. Setton
                                            Title  Treasurer

                                          GUARANTORS

                                         PLEXUS SERVICES CORP.

                                         By    /s/ George W.F. Setton
                                           ----------------------------------
                                            George W.F. Setton
                                            Treasurer

                                         PLEXUS ELECTRONIC ASSEMBLY CORP.

                                         By    /s/ George W.F. Setton
                                           ----------------------------------
                                            George W.F. Setton
                                            Treasurer

                                         PLEXUS INTL. SALES & LOGISTICS, LLC

                                         By    /s/ George W.F. Setton
                                           ----------------------------------
                                            George W.F. Setton
                                            Treasurer

                                         PLEXUS QS, LLC

                                         By     /s/ George W.F. Setton
                                           ----------------------------------
                                            George W.F. Setton
                                            Treasurer

                                      -4-
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                                     PLEXUS TECHNOLOGY GROUP INC.

                                     By    /s/ George W.F. Setton
                                       ---------------------------------------
                                        George W.F. Setton
                                        Treasurer

                                     PLEXUS INTERNATIONAL SERVICES, INC.

                                     By    /s/ Angelo Ninivaggi
                                       ---------------------------------------
                                        Angelo Ninivaggi
                                        President

                                     PTL INFORMATION TECHNOLOGY SERVICES CORP.

                                     By    /s/ Angelo Ninivaggi
                                       ---------------------------------------
                                        Angelo Ninivaggi
                                        President

                                      -5-
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                             LENDERS

                             HARRIS TRUST AND SAVINGS BANK, in its
                                individual capacity as a Lender and as
                                Administrative Agent

                             By    /s/ George M. Kluhy
                                ----------------------------------------------
                                Name  George M. Kluhy
                                Title  Vice President

                             LASALLE BANK NATIONAL ASSOCIATION

                             By    /s/ Lou D. Banach
                                ----------------------------------------------
                                Name  Lou D. Banach
                                Title  First Vice President & Senior Lender

                             NATIONAL CITY BANK

                             By    /s/ Tiffany Cozzolino
                                ----------------------------------------------
                                Name  Tiffany Cozzolino
                                Title  Vice President

                             THE BANK OF TOKYO - MITSUBISHI, LTD.,
                               CHICAGO BRANCH

                             By    /s/ Shinichiro Munechika
                                ----------------------------------------------
                                Name  Shinichiro Munechika
                                Title  Deputy General Manager

                             THE PROVIDENT BANK

                             By    /s/ Alan R. Henning
                                ----------------------------------------------
                                Name  Alan R. Henning
                                Title  Vice President

                                      -6-<PAGE>
                                                                 EXHIBIT 10.8(b)

                                  PLEXUS CORP.
                        2004 INCENTIVE COMPENSATION PLAN
                            EXECUTIVE LEADERSHIP TEAM

PLAN OBJECTIVES

The primary objectives of the 2004 Incentive Compensation Plan (Plan) are to
reward results delivered by plan participants that enhance shareholder value and
to assist Plexus Corp. (Plexus) to attract, retain and motivate highly qualified
and talented executives. The Plan provides annual variable incentive
compensation opportunities to participants for the achievement of specified
financial performance and other significant results that contribute to the
overall success of Plexus. Increasing revenues, improving financial returns on
capital employed, and achieving specific personal objectives are the three
performance elements of this Plan.

PLAN YEAR

The Plan Year is effective October 1, 2003 and continues through September 30,
2004.

ELIGIBILITY FOR PLAN PARTICIPATION

Participation in this Plan is limited to the members of the Plexus Executive
Leadership Team.

INCENTIVE PLAN COMPENSATION

Plan awards are to be calculated based upon the Plan Year base salary (salary
excluding bonuses, paid commissions, reimbursed relocation expenses, or any
other special pay, but including amounts deferred) of each participant adjusted
for pro-rations as applicable (See Award Payment Timing and Eligibility, below).
Incentive awards are calculated for each position (job) a participant holds
through the plan year and are pro-rated accordingly based on calendar weeks in
each position (FY 2004 = 52 weeks).

INCENTIVE PLAN PERFORMANCE MEASURES

The incentive performance measures, each of which stands independently of the
others with regard to award opportunities, are:

     *     REVENUES: Total Fiscal Year 2004 Net Sales of Plexus Corp.
     *     RETURN ON AVERAGE CAPITAL EMPLOYED (ROCE): Annual Operating Income
           for Fiscal Year 2004 divided by Average Capital Employed.  Where,
               *    OPERATING INCOME: As reported in the company's audited
                    income statement for Fiscal Year 2004 adjusted, if
                    necessary, to eliminate non-recurring or unusual charges.
               *    AVERAGE CAPITAL EMPLOYED: The 5 point average of the
                    year-end Fiscal Year 2003 and the quarterly Fiscal Year 2004
                    Capital Employed balances.
                        *    CAPITAL EMPLOYED: Total Assets (minus Cash) less
                             non-interest bearing Current and Non-current
                             Liabilities.

     *     OBJECTIVES: Individual participant assigned objectives that relate to
           personal or site/location/department measurable goals for the plan
           year, typically 3 to 5, which have been reviewed with and approved by
           the participant's supervisor.

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INCENTIVE PLAN PERFORMANCE AND REWARD OPPORTUNITIES

Incentive compensation is paid based on the following achievement levels,
resulting in a percentage determined according to the following matrix. That
percentage is then applied to a "target bonus" amount, which is set separately
for each individual.

<TABLE>
<CAPTION>

               COMPONENT                  THRESHOLD    PAYOUT       TARGET       PAYOUT        MAXIMUM        PAYOUT
---------------------------------------- ------------ ---------- ------------- ------------ -------------- -------------
<S>                                      <C>          <C>        <C>           <C>          <C>            <C>
                REVENUE                       (a)          0%           (a)        (a)%           (a)           (a)%

                 ROCE                         (a)          0%           (a)        (a)%           (a)           (a)%

          PERSONAL OBJECTIVES                              0%                      (a)%                         (a)%

           TOTAL INCENTIVE =                               0%                      100%                         200%
 REVENUES + ROCE + PERSONAL OBJECTIVES
---------------------------------------- ------------ ---------- ------------- ------------ -------------- -------------

</TABLE>

     (a) Specific threshold, target and maximum amounts, and percentages
         allocated to each component, are to be the same for each participant
         and determined with the approval of the Compensation and Leadership
         Development Committee; that information shall be communicated to
         eligible participants. Such determinations will be made on an annual
         basis, if it is decided to continue the Plan beyond fiscal 2004 (in
         which case all year references herein will be deemed to refer to the
         appropriate future year).

     *   THRESHOLD: At or below Revenue and/or ROCE Thresholds, only personal
         objectives awards can be earned. Revenue and ROCE measures begin
         producing incentive awards for above Threshold achievement.

     *   TARGET: Targets for the Revenue and ROCE measures relate to FY 2004
         financial performance goals. Personal objectives relate to individual
         participant performance and may reflect personal, location, site,
         department, or other measurable requirements. Awards will be pro-rated
         on a straight-line basis for performance that falls between Threshold
         and Target achievement.

     *   MAXIMUM: The maximum performance levels reflect the maximum award for
         each component. Awards will be pro-rated on a straight-line basis for
         performance that falls between Target and Maximum achievement.

Note:  No award will be paid for any component if the company incurs a net loss
for the fiscal year (excluding non-recurring or unusual charges).

AWARD PAYMENT TIMING AND ELIGIBILITY

Eligible participants will receive earned incentive awards no later than
December 15, 2004 (payment date). Adjustments occur under the following
circumstances:

     *   PARTICIPANT TRANSFER:  Awards will be pro-rated for participants who
         transfer between company organizations (sites, locations, departments,
         SBU's, etc.) based upon time spent in each job.

     *   PARTICIPANT STATUS CHANGE: Participants changing status (to/from
         eligible/ineligible position) are to be pro-rated by eligible weeks on
         the company payroll divided by the number of weeks of the plan year (FY
         2004 = 52 weeks).

     *   EMPLOYMENT/RE-EMPLOYMENT: New or rehired employees who enter the Plan
         after the start of the Plan Year will receive a pro-rated award based
         on the time actually in the Plan.

Page 2 of 3
<PAGE>

     *   EMPLOYMENT TERMINATION: Plan participants who leave the employ of
         Plexus (whether voluntarily or involuntarily) prior to the payout date
         (December 15, 2004), except in the case of retirement, disability,
         death or approval by the CEO, forfeit all rights to incentive awards
         accrued during the Plan Year.

     *   RETIREMENT, DISABILITY, OR DEATH: "Retirement" means eligible for
         retirement under Plexus Corp.'s retirement guidelines. Disability means
         eligible for disability benefits and unable to continue in the employ
         of the company due to such disability. In the event of death, any
         payable award will be paid to the participant's beneficiary(ies), or to
         the estate in the event that no beneficiary is named, following the end
         of the Plan Year. Awards for participants who leave due to retirement,
         disability or death will be pro-rated by eligible weeks on the company
         payroll divided by the number of weeks of the plan year (FY 2004 = 52
         weeks).

     *   NON-PERFORMING EMPLOYEES: If at any time during the plan year an
         individual's performance is not satisfactory and the participant is on
         a formal written performance improvement plan, such participant may be
         removed from this Plan, and either no award or a reduced award will be
         paid to the individual. Final approval of such action will be made by
         Executive Leadership.

     *   LEAVES OF ABSENCE: Awards for participants who are on an unpaid Leave
         of Absence will be pro-rated for the ROCE and Revenue components based
         upon eligible calendar weeks on the company payroll divided by the
         number of weeks of the plan year. (FY 2004 = 52 weeks)

COMMUNICATION

Each participant will receive a copy of this plan document and a Participant
Award Opportunity Summary, which will include the individual's target bonus
amount (which may be expressed as a dollar amount or as a percent of base
salary, as described above) and the specific threshold, target and maximum
amounts, and percentages allocated to each component (as described above). To
ensure understanding of the status of plan awards, Management will communicate
periodic performance trends and results to participants.

ADMINISTRATION

Overall policy direction shall be provided by the Board of Directors. Plan
administration shall be the responsibility of the CEO with support and guidance
from the Compensation and Leadership Development Committee of the Board of
Directors.

EXCEPTIONS AND REVISIONS

It is conceivable that there may be particular situations which are not properly
accommodated by the regular criteria and boundaries of the prevailing incentive
program, e.g. the effect that an acquisition, a secondary offering, or the like,
may have on Plexus' financial performance. Should such situation(s) occur, the
CEO will recommend appropriate adjustments to the Compensation and Leadership
Development Committee of the Board of Directors. If adjustments are made, the
reason for such adjustments will be set forth in the Committee's Minutes and
communicated to Plan participants. Nothing in this plan document or associated
communications in any way promises or guarantees the compensation or employment
of any participant with Plexus Corp. or any successor or related company(ies).

Page 3 of 3

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