<PAGE>
 
                               BACK SIDE OF PROXY

  THIS PROXY, WHEN PROPERLY EXECUTED, WILL BE VOTED IN ACCORDANCE WITH THE
SPECIFIC INDICATIONS ON THE REVERSE SIDE.  IN THE ABSENCE OF SUCH INDICATIONS,
THIS PROXY WILL BE VOTED FOR THE ENERGY INDUSTRIES SALE PROPOSAL AND FOR THE
CIMARRON SALE PROPOSAL, AND IN ACCORDANCE WITH THE JUDGMENT OF THE PERSON VOTING
THE PROXY WITH RESPECT TO ANY OTHER BUSINESS PROPERLY BEFORE THE SPECIAL
MEETING.

  THE UNDERSIGNED ACKNOWLEDGE(S) RECEIPT OF THE NOTICE OF THE AFORESAID SPECIAL
MEETING AND THE PROXY STATEMENT ACCOMPANYING THE SAME, EACH DATED OCTOBER ___,
1995.



                         -----------------------------------------
                         PRINTED NAME


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

                         SIGNATURE


                                                             , 1995
                         ------------------------------------
                         DATE
 
                         (Please sign exactly as your name appears hereon.  When
                         signing as attorney, executor, administrator, trustee,
                         guardian, etc., give your full title as such.  For
                         joint accounts, each joint owner should sign.)



                     PLEASE MARK, SIGN, DATE AND RETURN THE
                     PROXY CARD USING THE ENCLOSED ENVELOPE


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