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                                                                   Exhibit 3.5.3


Microfilm Number            Filed with the Department of State on Dec. 22, 1998
                 ----------                                       -------------
Entity Number 2613157       /s/ illegible       
              ------------- ---------------------------------------------------
                                     Secretary of the Commonwealth


                ARTICLES OF MERGER-DOMESTIC BUSINESS CORPORATION
                             DSCB:15-1926 (Rev 90)

        In compliance with the requirements of 15 Pa.C.S. Section 1926 
(relating to articles of merger or consolidation), the undersigned busines
corporations, desiring to effect a merger, hereby state that:

1. The name of the corporation surviving the merger is:    Werner Co. 
                                                        -----------------------

------------------------------------------------------------------------------

2. (CHECK AND COMPLETE ONE OF THE FOLLOWING): 
X  The surviving corporation is a domestic business corporation and the 
---(a) ADDRESS of its current registered office in this Commonwealth or 
   (b) name of its commercial registered office provider and the county of 
       venue is (the Department is hereby authorized to correct the following 
       information to conform to the records of the Department):

   (a)     93 Werner Road  Greenville      PA      16125   Mercer
       ------------------------------------------------------------------------ 
       Number and Street       City      State      Zip    County

   (b) c/o: 
           --------------------------------------------------------------------
           Name of Commercial Registered Office Provider                County

   For a corporation represented by a commercial registered office provider, the
   county in (b) shall be deemed the county in which the corporation is located
   for venue and official publication purposes.

__ The surviving corporation is a qualified foreign business corporation
   incorporated under the laws of __________________ and the (a) ADDRESS of its
   current registered office in this Commonwealth or (b) NAME of its commercial
   registered office provider and the county of venue is (the Department is
   hereby authorized to correct the following information to conform to the
   records of the Department):

   (a)
      -------------------------------------------------------------------------
       Number and Street       City      State      Zip    County

   (b) c/o:
           --------------------------------------------------------------------
           Name of Commercial Registered Office Provider                County

   For a corporation represented by a commercial registered office provider, the
   county in (b) shall be deemed the county in which the corporation is located
   for venue and official publication purposes.

__ The surviving corporation is a nonqualified foreign business corporation
   incorporated under the laws of _______________ and the address of its
   principal office under the laws of such domiciliary jurisdiction is:

      -------------------------------------------------------------------------
       Number and Street              City            State          Zip    

3. The NAME and the ADDRESS of the registered office in this Commonwealth or
   NAME of its commercial registered office provider and the county of venue of
   each other domestic business corporation and qualified foreign business
   corporation which is a party to the plan of merger are as follows:

                                ADDRESS OF REGISTERED OFFICE 
                                   OR NAME OF COMMERCIAL 
   NAME OF CORPORATION            REGISTERED OFFICE PROVIDER            COUNTY

   OLYMPUS PROPERTIES, INC.           c/o WERNER CO.                    Mercer
                                          93 Werner Road
                                          Greenville, PA 16125


<PAGE>   2
DSCB:15-1926 (Rev 90)-2


4. (Check, and if appropriate complete, one of the following):

   __ The plan of merger shall be effective upon filing these Articles of 
      Merger in the Department of State.

   X  The plan of merger shall be effective on:    December 31, 1998        
  ---                                           -------------------------------
      at         11:59 p.m.                              Date
         ------------------------------------
                   Hour

5. The manner in which the plan of merger was adopted by each domestic
   corporation is as follows:

    Name of Corporation                       Manner of Adoption

         Werner Co.               Adopted by the Board of Directors and Sole 
                                  Shareholder pursuant to 15 PA C.S. 
                                  Section 1924 (a)



6. (Strike out this paragraph if no foreign corporation is a party to the
   merger). The plan was authorized, adopted or approved, as the case may be, by
   the foreign business corporation (or each of the foreign business
   corporations) party to the plan in accordance with the laws of the
   jurisdiction in which it is incorporated.

7. (Check, and if appropriate complete, one of the following):

   X  The plan of merger is set forth in full in Exhibit A attached hereto and 
  --- made a part hereof.

      Pursuant to 15 Pa.C.S. Section 1901 (relating to omission of certain  
  --- provisions from filed plans) the provisions, if any, of the plan of 
      merger that amend or constitute the operative Articles of Incorporation
      of the surviving corporation as in effect subsequent to the effective
      date of the plan are set forth in full in Exhibit A attached hereto and
      made a part hereof. The full text of the plan of merger is on file at the
      principal place of business of the surviving corporation, the address of  
      which is:

      ------------------------------------------------------------------------
      Number and Street            City              State      Zip     County 

      IN TESTIMONY WHEREOF, the undersigned corporation or each undersigned
corporation has caused these Articles of Merger to be signed by a duly
authorized officer thereof this 15th day of December, 1998.

                                        Werner Co.
                                        ----------------------------------------
                                                (Name of Corporation)

                                     BY: /s/ Donald M. Werner 
                                        ----------------------------------------
                                                      (Signature)

                                  TITLE: President and Chief Executive Officer
                                        ----------------------------------------

                                        OLYMPUS PROPERTIES, INC.
                                        ----------------------------------------
                                                (Name of Corporation)

                                     BY: /s/ Eric ?. Werner
                                         ---------------------------------------
                                                     (Signature)

                                  TITLE: President and Chief Executive Officer
                                         ---------------------------------------



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                                  EXHIBIT "A"

                                 PLAN OF MERGER



        The following is the Plan of Merger for merging OLYMPUS PROPERTIES,
INC., an Illinois corporation ("OLYMPUS") into WERNER CO., a Pennsylvania
corporation ("WERNER") as approved on December 15, 1998 by resolution of the
Boards of Directors and Shareholders of OLYMPUS and WERNER.

        1.      OLYMPUS shall, pursuant to the provisions of the Business
                Corporation Law of 1988 of the Commonwealth of Pennsylvania, as
                amended, and the Business Corporation Act of 1983 of the State
                of Illinois, as amended, be merged into WERNER, which shall be
                the surviving corporation upon the effective date of the merger
                in the Commonwealth of Pennsylvania and which shall continue to
                exist as said surviving corporation pursuant to the provisions
                of the Business Corporation Law of 1988 of the Commonwealth of
                Pennsylvania, as amended. The separate existence of OLYMPUS,
                shall cease upon the effective date of the merger in accordance
                with the provisions of the Business Corporation Act of the State
                of Illinois, as amended.

        2.      The Articles of Incorporation and Bylaws of WERNER upon the
                effective date of the merger in the Commonwealth of Pennsylvania
                shall be the Articles of Incorporation and Bylaws of the
                surviving corporation.

        3.      The directors and officers of WERNER in office upon the
                effective date of the merger shall be the members of the first
                Board of Directors and the first officers of the surviving
                corporation, all of whom shall hold their directorships and
                offices until the election and qualification of their respective
                successors or until their tenure is otherwise terminated in
                accordance with the by-laws of the surviving corporation.

        4.      The issued shares of capital stock of OLYMPUS shall not be
                converted or exchanged in any manner, but each said share which
                is issued as of the effective time and date of the merger shall
                be cancelled and retired. The issued shares of capital stock of
                WERNER shall not be changed as a result of the merger.

        5.      The merger shall become effective at 11:59p.m. on December 31,
                1998.

        6.      The Boards of Directors and the officers of OLYMPUS and of
                WERNER are hereby authorized, empowered, and directed to do any
                and all acts and things, and to make, execute, deliver, file,
                and/or record any and all instruments, papers, and documents
                which shall be or become necessary, proper, or convenient to
                carry out or put into effect any of the provisions of this Plan
                of Merger or of the merger herein provided for.