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                                                                 Exhibit 3.7 (d)

                            CERTIFICATE OF AMENDMENT

                                       OF

                            ARTICLES OF INCORPORATION

                  MID-FLORIDA STEEL CORPORATION, a Florida corporation, under
its corporate seal and the hands of its president, E. C. ADDISON, and
secretary, D. ARTHUR YERGEY, hereby certify that:

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                  The Board of Directors of said corporation, at a meeting
called and held on November 19, 1962, adopted the following resolution amending
Article III of the Articles of Incorporation:

                  "Be it resolved that the Board of Directors of Mid-Florida
                  Steel Corporation, a Florida corporation, deems it advisable
                  and hereby declares it to be advisable that Article III of the
                  Articles of Incorporation of said corporation be amended and
                  changed and altered so as to read as follows: The capital
                  stock of this corporation shall be as follows:

                  a. Common stock - $40,000. which shall be divided into 8,000
                  shares of common stock of a par value of $5.00 per share, all
                  of which is to be fully paid and non-assessable. Said common
                  stock, or any portion thereof, may be paid for in property,
                  labor or services at a just valuation fixed by the
                  incorporators or the directors at a meeting called for that
                  purpose.

                  b. Preferred Stock - $20,000. which shall be divided into
                  2,000 shares of preferred stock at a par value of $10.00 per
                  share, bearing interest payable annually at the rate of 7
                  1/2%. Said stock shall be due and callable three (3) years
                  from date of issuance. Said preferred stock may be paid for
                  only in cash and no discount upon the purchase price thereof,
                  if any, shall exceed 2 1/2% of the face amount of the par
                  value of said stock. Said preferred stock may be issued only
                  upon the unanimous vote of all of the stockholders and
                  directors of said corporation. The three year period of said
                  stock can only be extended 


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                  upon a like unanimous vote of all of the stockholders and
                  directors of said corporation, at a meeting called for that
                  purpose.

                                       II

                  A meeting of the officers, directors and stockholders of the
said corporation was called by the President and was held on November 19th, 1962
and at said special meeting of officers, directors and stockholders, said
amendment of the Certificate of Incorporation was duly adopted by unanimous vote
of all the officers, directors and stockholders.

                  IN WITNESS WHEREOF, corporation has caused this certificate to
be signed by its President and attested by its Secretary, this 19th day of
November, 1962.

                                              MID-FLORIDA STEEL CORPORATION

                                              By
                                                  /s/  E.C. Addison 
                                                  --------------------------
                                                  E. C. Addison, President

ATTEST:
/s/  D. Arthur Yergey                               (CORPORATE SEAL)
-------------------------------
D. Arthur Yergey, Secretary


Signed, sealed and delivered 
in the presence of:


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STATE OF FLORIDA  )
                  ) ss
COUNTY OF ORANGE  )

                  I HEREBY CERTIFY that on this day before me, an officer duly
authorized in the state aforesaid and in the county aforesaid, to take
acknowledgments, personally appeared

                  E. C. ADDISON and D. ARTHUR YERGEY

to me known to be the persons described in and who executed the foregoing
Certificate of Amendment of Articles of Incorporation and they severally
acknowledged before me that they executed the above and foregoing instrument for
the uses and purpose therein expressed.

                  IN WITNESS WHEREOF, I have hereunto set my hand and official
seal at Orlando, Orange County, Florida, the day and year first above written.



                                            ------------------------------
                                                      Notary Public



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