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                                                                 EXHIBIT 10.8(b)
                                                                       2004 10-K
                                  PLEXUS CORP.
                    2005 VARIABLE INCENTIVE COMPENSATION PLAN
                            EXECUTIVE LEADERSHIP TEAM



PLAN OBJECTIVES

The primary objectives of the 2005 Variable 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, 2004 and continues through October 1,
2005.

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 2005 = 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 2005 Net Sales of Plexus Corp.

     -    RETURN ON AVERAGE CAPITAL EMPLOYED (ROCE): Annual Operating Income for
          Fiscal Year 2005 divided by Average Capital Employed. Where,

          -    OPERATING INCOME: As reported in the company's audited income
               statement for Fiscal Year 2005 adjusted, if necessary, to
               eliminate non-recurring or unusual charges.

          -    AVERAGE CAPITAL EMPLOYED: The 5 point average of the year-end
               Fiscal Year 2004 and the quarterly Fiscal Year 2005 Capital
               Employed balances.

               -    CAPITAL EMPLOYED: Total Assets (minus Cash) less
                    non-interest bearing Current and Non-current Liabilities.

     -    OBJECTIVES: Individual participant objectives that relate to
          measurable personal or site/location/department goals for the plan
          year; typically the number of goals should be limited to 3 to 5, which
          have been developed with, reviewed by 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:
<TABLE>
<CAPTION>

               COMPONENT                   THRESHOLD    PAYOUT       TARGET       PAYOUT       MAXIMUM       PAYOUT
---------------------------------------- -------------- -------- --------------- ---------- --------------- ---------
<S>                                      <C>            <C>      <C>             <C>        <C>             <C>
                REVENUE                       $ *         0%          $ *           40%          $ *           40%
                 ROCE                           *%        0%            *%          40%            *%         140%
          PERSONAL OBJECTIVES                             0%                        20%                        20%
           TOTAL INCENTIVE =                              0%                       100%                       200%
 REVENUES + ROCE + PERSONAL OBJECTIVES

</TABLE>

     *    Specific threshold, target and maximum amounts, and percentages
          allocated to each component, are 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. If it is decided to continue the Plan beyond
          fiscal 2005, all year references herein will be deemed to refer to the
          appropriate future year and numbers in this matrix will be re-set for
          such years.]
     -    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 the FY
          2005 financial plan. Personal objectives relate to individual
          participant performance and may reflect personal, location, site,
          department, or other measurable objectives. 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, 2005 (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 2005 = 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.



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     -    EMPLOYMENT TERMINATION: Plan participants who leave the employ of
          Plexus (whether voluntarily or involuntarily) prior to the payout date
          (December 15, 2005), 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 2005 = 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. Approval of such action will be made by the
          CEO subject to the final approval of the Compensation and Leadership
          Development Committee of the Board.
     -    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 2005 = 52 weeks)


COMMUNICATION

Each participant will receive a copy of this plan document and a Participant
Award Opportunity Summary. 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 stock 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).



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