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                                                                    Exhibit 10.6

                                   TISM, INC.

                  FOURTH AMENDED AND RESTATED STOCK OPTION PLAN

                (AS AMENDED AND RESTATED EFFECTIVE JUNE 25, 2003)

     WHEREAS, TISM, Inc. (the "Company") adopted a stock option plan known as
the TISM, Inc. Stock Option Plan (the "Plan") for the benefit of eligible
employees as determined from time to time by its Board of Directors; and

     WHEREAS, the Company has amended and restated the Plan before; and

     WHEREAS, the Company desires to further amend and restate the Plan,
effective June 25, 2003.

     NOW, THEREFORE, the Plan is hereby amended and restated in its entirety
effective June 25, 2003.

1.   PURPOSE

     The purpose of this Stock Option Plan (the "Plan") is to advance the
interests of TISM, Inc., a Michigan corporation (the "Company"), by enhancing
the ability of the Company and its subsidiaries (if any) to attract and retain
able employees and directors of the Company and its subsidiaries; to reward such
individuals for their contributions; and to encourage such individuals to take
into account the long-term interests of the Company and its subsidiaries through
interests in shares of the Company's Common Stock, $.001 par value per share
(the "Stock"). Any employee or director selected to receive an award under the
Plan is referred to as a "participant."

2.   ADMINISTRATION

     The Plan shall be administered by the Board of Directors (the "Board") of
the Company. Subject to the applicable law, the Board shall have discretionary
authority, not inconsistent with the express provisions of the Plan, (a) to
grant option awards to such eligible persons as the Board may select; (b) to
determine the time or times when awards shall be granted and the number of
shares of Stock subject to each award; (c) to determine the terms and conditions
of each award; (d) to prescribe the form or forms of any instruments evidencing
awards and any other instruments required under the Plan and to change such
forms from time to time; (e) to adopt, amend, and rescind rules and regulations
for the administration of the Plan; and (f) to interpret the Plan and to decide
any questions and settle all controversies and disputes that may arise in
connection with the Plan. Such determinations of the Board shall be conclusive
and shall bind all parties. Subject to Section 9, the Board shall also have the
authority, both generally and in particular instances, to waive compliance by a
participant with any obligation to be performed by him or her under an award, to
waive any condition or provision of an award, and to amend or cancel any award
(and if an award is canceled, to grant a new award on such terms as the Board
shall specify), except that the Board may not take any action with respect to an
outstanding award that would adversely affect the rights of the participant
under such award without such participant's consent. Nothing in the preceding
sentence shall be construed as limiting the power of the Board to make
adjustments required by Section 4(c) and Section 6(g).

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     The Board may, in its discretion, delegate some or all of its powers with
respect to the Plan to a committee (the "Committee"), in which event all
references (as appropriate) to the Board hereunder shall be deemed to refer to
the Committee. The Committee, if one is appointed, shall consist of at least two
directors. A majority of the members of the Committee shall constitute a quorum,
and all determinations of the committee shall be made by a majority of its
members. Any determination of the Committee under the Plan may be made without
notice or meeting of the Committee by a writing signed by a majority of the
Committee members. On and after registration of the Stock under the Securities
Exchange Act of 1934, as amended (the "1934 Act"), the Board shall delegate the
power to select directors and officers to receive awards under the Plan and the
timing, pricing, and amount of such awards to a Committee, all members of which
shall be "non-employee directors" within the meaning of Rule 16b-3 under the
1934 Act and "outside directors" within the meaning of Section 162(m)(4)(c)(i)
of the Internal Revenue Code of 1986, as amended (the "Code"), in which event
all references (as appropriate) to the Board hereunder shall be deemed to refer
to the Committee.

3.   EFFECTIVE DATE AND TERM OF PLAN

     The Plan became effective on December 21, 1998, and was approved by the
stockholders of the Company. Grants of awards under the Plan made prior to that
date (but after Board adoption of the Plan), were subject to approval of the
Plan by the stockholders.

     No awards shall be granted under the Plan after the completion of 10 years
from the date on which the Plan was initially adopted by the Board, but awards
previously granted may extend beyond that date.

4.   SHARES SUBJECT TO THE PLAN

     (a) Number of Shares. Subject to adjustment as provided in Section 4(c),
the aggregate number of shares of Stock that may be the subject of awards
granted under the Plan shall be 9,836,739 shares of Class A-3 Common Stock and
62,576 shares of Class L Common Stock. If any award granted under the Plan
terminates without having been exercised in full, or upon exercise is satisfied
other than by delivery of Stock, the number of shares of Stock as to which such
award was not exercised shall be available for future grants.

     (b) Shares to be Delivered. Shares delivered under the Plan shall be
authorized but unissued Stock, or if the Board so decides in its sole
discretion, previously issued Stock acquired by the Company and held in its
treasury. No fractional shares of Stock shall be delivered under the Plan.

     (c) Changes in Stock. In the event of a stock dividend, stock split or
combination of shares, recapitalization, or other transaction or event that
affects the Company's capital stock, the number and kind of shares of stock or
securities of the Company subject to awards then outstanding or subsequently
granted under the Plan, the exercise price of such awards, the maximum number of
shares or securities that may be delivered under the Plan, and other relevant
provisions shall be appropriately adjusted to prevent enlargement or dilution of
benefits intended to be made available under the Plan by the Board, whose
determination shall be binding on all persons.

     The Board may in good faith also adjust the number of shares subject to
outstanding awards, the exercise price of outstanding awards, and the terms of
outstanding awards, to take into consideration material changes in accounting
practices or principles, extraordinary dividends,


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consolidations or mergers (except those described in Section 6(g)), acquisitions
or dispositions of stock or property, or any other event if it is determined by
the Board that such adjustment is appropriate to avoid distortion in the
operation of the Plan.

5.   ELIGIBILITY AND PARTICIPATION

     Persons eligible to receive awards under the Plan shall be those persons
who, in the opinion of the Board, are in a position to make a significant
contribution to the success of the Company and its subsidiaries. A subsidiary
for purposes of the Plan shall be a corporation in which the company owns,
directly or indirectly, stock possessing 50% or more of the total combined
voting power of all classes of stock.

6.   TERMS AND CONDITIONS

     (a) Exercise Price of Options. The exercise price of each option shall be
determined by the Board, but the exercise price shall not be less, in the case
of an original issue of authorized stock, than par value.

     (b) Duration of Options. An option shall be exercisable during such period
or periods as the Board may specify. The latest date on which an option may be
exercised (the "Expiration Date") shall be the date that is 10 years from the
date the option was granted or such earlier date as may be specified by the
Board at the time the option is granted.

     (c) Exercise of Options.

          (1) An option shall become exercisable at such time or times and upon
     such conditions as the Board shall specify. In the case of an option not
     immediately exercisable in full, the Board may at any time accelerate the
     time at which all or any part of the option may be exercised.

          (2) Any exercise of an option shall be in writing by the proper person
     and furnished to the Company, accompanied by (A) such documents as may be
     required by the Board and (B) payment in full as specified below in Section
     6(d) for the number of shares for which the option is exercised.

          (3) The Board shall have the right to require that the participant
     exercising the option remit to the Company an amount sufficient to satisfy
     any federal, state, or local withholding tax requirements (or make other
     arrangements satisfactory to the Company with regard to such taxes) prior
     to the delivery of any Stock pursuant to the exercise of the option. If
     permitted by the Board, either at the time of the grant of the option or in
     connection with exercise, the participant may elect, at such time and in
     such manner as the Board may prescribe, to satisfy such withholding
     obligation by (A) delivering to the Company Stock owned by such individual
     having a fair market value equal to such withholding obligation, or (B)
     requesting that the Company withhold from the shares of Stock to be
     delivered upon the exercise a number of shares of Stock having a fair
     market value equal to such withholding obligation.


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          In addition, if at the time the option is exercised the Board
     determines that under applicable law and regulations the Company could be
     liable for the withholding of any federal or state tax with respect to a
     disposition of the Stock received upon exercise, the Board may require as a
     condition of exercise that the participant exercising the option agree to
     give such security as the Board deems adequate to meet the potential
     liability of the Company for the withholding of tax, and to augment such
     security from time to time in any amount reasonably deemed necessary by the
     Board to preserve the adequacy of such security.

          (4) If an option is exercised by the executor or administrator of a
     deceased participant, or by the person or persons to whom the option has
     been transferred by the participant's will or the applicable laws of
     descent and distribution, the Company shall be under no obligation to
     deliver Stock pursuant to such exercise until the Company is satisfied as
     to the authority of the person or persons exercising the option.

     (d) Payment for and Delivery of Stock. Stock purchased upon exercise of an
option under the Plan shall be paid for as follows: (1) in cash, check
acceptable to the Company (determined in accordance with such guidelines as the
Board may prescribe), or money order payable to the order of the Company; (2) by
the Company retaining from the shares of Stock to be delivered upon exercise of
the Option that number of shares of Stock having a fair market value on the date
of exercise equal to the option price of the number of shares of Stock with
respect to which the participant or other eligible person exercises the option,
or (3) if so permitted by the Board, (A) through the delivery of shares of Stock
(which, in the case of Stock acquired from the Company, shall have been held for
at least 6 months unless the Board specifies a shorter period) having a fair
market value on the last business day preceding the date of exercise equal to
the purchase price, or (B) by delivery of a promissory note of the participant
to the Company, such note to be payable on such terms as are specified by the
Board, or (C) by delivery of an unconditional and irrevocable undertaking by a
broker to deliver promptly to the Company sufficient funds to pay the exercise
price, or (D) by any combination of the permissible forms of payment; provided,
that if the Stock delivered upon exercise of the option is an original issue of
authorized Stock, at least so much of the exercise price as represents par value
of such Stock shall be paid other than with a personal check or promissory note
of the person exercising the option.

     (e) Delivery of Stock. A participant shall not have the rights of a
stockholder with regard to awards under the Plan except as to Stock actually
received by him under the Plan.

     The Company shall not be obligated to deliver any shares of Stock (1)
until, in the opinion of the Company's counsel, all applicable federal and state
laws and regulations have been complied with, (2) if the outstanding Stock is at
the time listed on any stock exchange, until the shares to be delivered have
been listed or authorized to be listed on such exchange upon official notice of
issuance, and (3) until all other legal matters in connection with the issuance
and delivery of such shares have been approved by the Company's counsel. Without
limiting the generality of the foregoing, if the sale of Stock has not been
registered under the Securities of 1933, as amended, the Company may require, as
a condition to exercise of the award, such representations or agreements as
counsel for the Company may consider appropriate to avoid violation of such Act
and may require that the certificates evidencing such Stock bear an appropriate
legend restricting transfer.


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     (f) Nontransferability of Awards. Except as specifically provided in an
option approved by the Board, no option or other award may be transferred other
than by will or by the laws of descent and distribution, and during a
participant's lifetime an award may be exercised only him or her.

     (g) Mergers, etc. In the event of any merger, consolidation, dissolution,
or liquidation of the Company, the Board in its sole discretion may, as to any
outstanding options or other awards, make such substitution or adjustment in the
aggregate number of shares reserved for issuance under the Plan and in the
number and purchase price (if any) of shares subject to such awards as it may
determine, or accelerate, amend, or terminate such awards upon such terms and
conditions as it shall provide (which, in the case of the termination of the
vested portion of any award, shall require payment or other consideration that
the Board deems equitable in the circumstances).

7.   TERMINATION OF EMPLOYMENT OR BOARD MEMBERSHIP

     (a) If a participant's employment or service as a member of the Board with
the Company and its subsidiaries terminates prior to the Expiration Date, the
Board in its sole discretion may provide (either prior to or within 30 days
following termination) that (1) any or all of such portion of any option not
otherwise vested (i.e., exercisable) prior to termination shall be treated as
having become vested immediately prior to termination, in which case, as to that
number of shares of Stock for which the award was vested, or deemed vested by
action of the Board, immediately prior to termination, such award shall continue
to be exercisable thereafter during the period prior to the Expiration Date and
within one year following the termination; or (2) except if otherwise set forth
in an award, the participant or beneficiary receive in cash, with respect to
each share of Stock to which an option or other award relates, the excess of (x)
the share's fair market value on the date of the participant's termination over
(y) the option exercise price. Except as otherwise provided in an award, after
completion of the one-year period, such awards shall terminate to the extent not
previously exercised, expired, or terminated. No option shall be exercised or
surrendered in exchange for a cash payment after the Expiration Date.

     (b) Notwithstanding the foregoing, except as otherwise provided in an
award, if the participant is terminated for "cause" (as defined in (c) below),
all options and other awards shall immediately terminate as to all shares of
Stock subject hereto, whether or not vested immediately prior to such
termination for cause.

     (c) "Cause," with respect to any participant who is an employee of the
Company and its subsidiaries, shall mean the following events or conditions: (1)
the failure to devote substantially all of his or her business time to the
performance of his or her duties to the Company or any of its subsidiaries
(other than by reason of disability), or refusal or failure to follow or carry
out any reasonable direction of the Board of Directors, and the continuance of
such refusal or failure for a period of 10 days after notice to such
participant; (2) the material breach by the participant of any material
agreement to which such participant and the Company or any of its affiliates are
a party; (3) the commission of fraud, embezzlement, theft or other dishonesty by
such participant with respect to the Company or any of its affiliates; (4) the
conviction of such participant of, or plea by such participant of nolo
contendere to, any felony or any other crime involving dishonesty or moral
turpitude; and (5) any other intentional action or intentional omission that
involves a material breach of fiduciary obligation on the part of such
participant.


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     (d) The Board may provide in the case of any award for post-termination
exercise provisions different from those expressly set forth in this Section 7,
including with limitation terms allowing a later exercise by a former employee
or director (or, in the case of a former employee or director who is deceased,
the person or persons to whom the award is transferred by will or the laws of
descent and distribution) as to all or any portion of the award not exercisable
immediately prior to termination of employment or service as a director, but in
no case may an award be exercised after the Expiration Date.

8.   EMPLOYMENT OR DIRECTORSHIP RIGHTS

     Neither the adoption of the Plan nor the grant of awards shall confer upon
any participant any right to continue as an employee or director of the Company,
its parent, or any subsidiary or affect in any way the right of the Company, its
parent, or a subsidiary to terminate the participant's relationship at any time.
Except as specifically provided by the Board in any particular case, the loss of
existing or potential profit in awards granted under this Plan shall not
constitute an element of damages in the event of termination of the relationship
of a participant.

9.   EFFECT, DISCONTINUANCE, CANCELLATION, AMENDMENT, AND TERMINATION

     Neither adoption of the Plan nor the grant of awards to a participant shall
affect the Company's right to make awards to such participant that are not
subject to the Plan, to issue to such participant Stock as a bonus or otherwise,
or to adopt other plans or arrangement under which Stock may be issued. No
option granted pursuant to the Plan is intended to be an incentive stock option
under Section 422 of the Code.

     The Board may at any time or times amend the Plan or any outstanding award
for the purpose of satisfying the requirements of any changes in applicable laws
or regulations or for any other purpose that may at the time be permitted by
law, or may at any time terminate the Plan as to any further grants of awards;
provided, that, except to the extent expressly required by the Plan, no such
amendment shall adversely affect the rights of any participant (without his or
her consent) under any award previously granted, nor shall such amendment,
without the approval of the stockholders of the Company, effectuate a change for
which stockholder approval is required to comply with any tax or regulatory
requirement, including in order for the Plan to continue to qualify under Rule
16b-3 promulgated under Section 16 of the 1934 Act.

10.  MISCELLANEOUS

     The Plan shall be governed by Michigan law. The Board may provide in a
particular case that an award shall be evidenced by an award agreement or
certificate.

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