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                                                                    EXHIBIT 3.20


                            ARTICLES OF INCORPORATION

                     For Use by Domestic Profit Corporations



     Pursuant to the provisions of Act 284, Public Acts of 1972, as amended, the
undersigned corporation executes the following Articles:


                                    ARTICLE I

     The name of the corporation is RPI Holdings, Inc.


                                   ARTICLE II


     The purpose or purposes for which the corporation is formed is to engage in
any activity within the purposes for which corporations may be formed under the
Business Corporation act of Michigan.


                                   ARTICLE III


     The total authorized shares are 60,000.


                                   ARTICLE IV


     The address and mailing address of the registered office is:  505 North
Woodward Avenue, Suite 3000, Bloomfield Hills, Michigan  48304-2967.  The name
of the resident agent at the registered office is Rex. E. Schlaybaugh, Jr.


                                    ARTICLE V


     The name and address of the incorporator is:  Stuart D. Logan, 400
Renaissance Center, L-2, Detroit, Michigan  48243.


                                   ARTICLE VI


     When a compromise or arrangement or a plan of reorganization of this
corporation is proposed between this


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corporation and its creditors or any class of them or between this corporation
and its shareholders or any class of them, a court of equity jurisdiction within
the state, on application of this corporation or of a creditor or shareholder
thereof, or on application of a receiver appointed for the corporation, may
order a meeting of the creditors or class of creditors or of the shareholders or
class of shareholders to be affected by the proposed compromise or arrangement
or reorganization, to be summoned in such manner as the court directs. If a
majority in number representing three-fourths in value of the creditors or class
of creditors, or of the shareholders or class of shareholders to be affected by
the proposed compromise or arrangement or a reorganization agree to a compromise
or arrangement or a reorganization of this corporation as a consequence of the
compromise or arrangement, the compromise or arrangement and the reorganization,
if sanctioned by the court to which the application has been made, shall be
binding on all the creditors or class of creditors, or on all the shareholders
or class of shareholders and also on this corporation.


                                   ARTICLE VII


     Any action required or permitted by the Act to be taken at an annual or
special meeting of shareholders may be taken without a meeting, without prior
notice and without a vote, if consents in writing, setting forth the action so
taken, are signed by the holders of outstanding shares having not less than the
minimum number of votes that would be necessary to authorize or take the action
at a meeting at which all shares entitled to vote on the action were present and
voted. The written consents shall bear the date of signature of each shareholder
who signs the consent. No written consent shall be effective to take the
corporate action referred to unless, within 60 days after the record date for
determining shareholders entitled to express consent to or to dissent from a
proposal without a meeting, written consents signed by a sufficient number of
shareholders to take the action are delivered to the corporation. Delivery shall
be to the corporation's registered office, its principal place of business, or
an officer or agent of the corporation having custody of the minutes of the
proceedings of its shareholders. Deliveries made to a corporation's registered
office shall be by hand or by certified or registered mail, return receipt
requested.

     Prompt notice of the taking of the corporate action without a meeting by
less than unanimous written consent shall be given to shareholders who have not
consented in writing.


                                  ARTICLE VIII


     The corporation shall not be governed by Chapter 7a of the Michigan
Business Corporation Act. This Article VIII may be altered, amended or repealed
by the affirmative vote of a majority of the outstanding shares of stock of the
corporation entitled to vote thereon.




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                                   ARTICLE IX


     No director of the corporation shall be personally liable to the
corporation or its shareholders for monetary damages for breach of fiduciary
duty as a director, provided that the foregoing shall not eliminate or limit the
liability of a director for any of the following: (i) a breach of the director's
duty of loyalty to the corporation or its shareholders, (ii) acts or omissions
not in good faith or that involve intentional misconduct or knowing violation of
law, (iii) a violation of Section 551(1) of the Michigan Business Corporation
Act or (iv) a transaction from which the director derived an improper personal
benefit. If the Michigan business Corporation Act hereafter is amended to
authorize the further elimination or limitation of the liability of directors,
then the liability of a director of the corporation, in addition to the
limitation on personal liability contained herein, shall be eliminated or
limited to the fullest extent permitted by the Michigan Business Corporation Act
as so amended. No amendment or repeal of this Article IX shall apply to or have
any effect on the liability or alleged liability of any director of the
corporation for or with respect to any acts or omissions of such director
occurring prior to the effective date of any such amendment or repeal.

     I, the incorporator, sign my name this 23rd day of July, 1993.


                                      /S/ Stuart D. Logan
                                         Stuart D. Logan