UNITED STATES
                    SECURITIES AND EXCHANGE COMMISSION
                          Washington, D.C.  20549


                               SCHEDULE 13G


                 Under the Securities Exchange Act of 1934

                       (Amendment No. _____6_____)*


                                 SPX Corp.
                             (Name of Issuer)

                      COMMON STOCK, $10.00 PAR VALUE
                      (Title of Class of Securities)

                                 784635104
                              (CUSIP Number)


Check the following box if a fee is being paid with this statement.
(A fee is not required only  if the filing person:  (1) has a previous
statement on  file reporting  beneficial  ownership of  more than five
percent of  the class of  securities described in  Item 1; and  (2) has filed
no amendment subsequent thereto reporting beneficial ownership of five
percent or less of such class.)  (See Rule 13d-7).

    *The remainder of  this cover page shall be filled  out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for  any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.

    The information required in the remainder of this  cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).



1  NAME OF REPORTING PERSON
   S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

   Forstmann-Leff Associates Inc.
   13-3131718

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                (a) 

                                                (b) 


3  SEC USE ONLY



4  CITIZENSHIP OR PLACE OF ORGANIZATION

   New York


                    5  SOLE VOTING POWER
   NUMBER OF
     SHARES            674,715 shares
  BENEFICIALLY
    OWNED BY        6  SHARED VOTING POWER
      EACH
    REPORTING          355,000 shares
     PERSON
      WITH
                    7  SOLE DISPOSITIVE POWER

                       906,615 shares

                    8  SHARED DISPOSITIVE POWER

                       583,600 shares

9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,504,615 shares (includes 14,400 shares as to which the reporting
     person has voting but no dispositive power)

10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES


11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

    10.8%

12  TYPE OF REPORTING PERSON

    IA, CO



1  NAME OF REPORTING PERSON
   S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

   FLA Asset Management, Inc.
   13-29256626

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                (a) 

                                                (b) 


3  SEC USE ONLY



4  CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware


                    5  SOLE VOTING POWER
   NUMBER OF
     SHARES            None
  BENEFICIALLY
    OWNED BY        6  SHARED VOTING POWER
      EACH
    REPORTING          90,300 shares
     PERSON
      WITH
                    7  SOLE DISPOSITIVE POWER

                       None

                    8  SHARED DISPOSITIVE POWER

                       318,900 shares

9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     318,900 shares 

10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES


11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

    2.3%

12  TYPE OF REPORTING PERSON

    IA, CO



1  NAME OF REPORTING PERSON
   S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

   Stamford Advisers Corp.
   13-3421430

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                (a) 

                                                (b) 


3  SEC USE ONLY



4  CITIZENSHIP OR PLACE OF ORGANIZATION

   New York


                    5  SOLE VOTING POWER
   NUMBER OF
     SHARES            None
  BENEFICIALLY
    OWNED BY        6  SHARED VOTING POWER
      EACH
    REPORTING          264,700 shares
     PERSON
      WITH
                    7  SOLE DISPOSITIVE POWER

                       None

                    8  SHARED DISPOSITIVE POWER

                       264,700 shares

9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     264,700 shares

10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES


11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

    1.9%

12  TYPE OF REPORTING PERSON

    IA, CO



Item 1(a)      NAME OF ISSUER:

               SPX Corp.

Item 1(b)      ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:

               700 Terrace Point Drive
               Muskegon, Michigan 49443

Item 2(a)      NAME OF PERSON FILING:

               See Item 1 of the cover pages attached hereto

Item 2(b)      Address of Principal Business Office, or if none, residence:

               55 East 52nd Street
               New York, New York  10055

Item 2(c)      CITIZENSHIP:

               See Item 4 of the cover pages attached hereto

Item 2(d)      TITLE OF CLASS OF SECURITIES:

               Common Stock, par value $10.00

Item 2(e)      CUSIP NUMBER:

               784635104

Item 3         Forstmann-Leff Associates Inc., a New York corporation, is a
               registered investment adviser under Section 203 of the
               Investment Advisers  Act of 1940  (the "Act").  FLA Asset
               Management, Inc. is a registered investment adviser under the
               Act and a subsidiary of Forstmann-Leff Associates Inc. 
               Stamford Advisers Corp. is a registered investment adviser
               under the Act and a subsidiary of Forstmann-Leff Associates
               Inc.

Item 4         OWNERSHIP:

               (a)  Amount beneficially owned:
                    See Item 9 of the cover pages attached hereto

               (b)  Percent of Class:
                    See Item 11 of the cover pages attached hereto

               (c)  See Items 5 through 8  of the cover pages attached hereto

Item 5         OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:

               Not Applicable

Item 6         OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER
               PERSON:

               Not Applicable

Item 7         IDENTIFICATION AND CLASSIFICATION  OF THE SUBSIDIARY WHICH 
               ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
               COMPANY:

               Not Applicable

Item 8         IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP:

               Not Applicable

Item 9         NOTICE OF DISSOLUTION OF GROUP:

               Not Applicable

Item 10        CERTIFICATION:

               By signing below I certify that, to the best of my knowledge
               and belief, the securities referred to above were acquired in
               the ordinary course of business and were not acquired for the
               purpose of and do not have the effect of changing or
               influencing the control of the issuer of such securities and
               were not acquired in connection with or as a participant in
               any transaction having such purposes or effect.



                                   SIGNATURES



After  reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set  forth in this statement is true, complete
and correct.


February 9, 1994


                                   FORSTMANN-LEFF ASSOCIATES INC.


                                   By:  /s/ Peter A. Lusk
                                        Peter A. Lusk
                                        Chief Operating Officer


                                   FLA ASSET MANAGEMENT, INC.


                                   By:  /s/ Peter A. Lusk
                                        Peter A. Lusk
                                        Executive Vice President
                                        and Chief Operating Officer



                                   STAMFORD ADVISERS CORP.


                                   By:  /s/ Peter A. Lusk
                                        Peter A. Lusk
                                        Vice President/Secretary


                                                                  Exhibit A


                                 AGREEMENT

               The undersigned, Forstmann-Leff Associates Inc., FLA Asset
Management, Inc. and Stamford Advisers Corp., agree that the statement to
which this exhibit is appended is filed on behalf of each of them.


February 9, 1994


                              FORSTMANN-LEFF ASSOCIATES INC.


                              By:  /s/ Peter A. Lusk                        
                                   Peter A. Lusk
                                   Chief Operating Officer


                              FLA ASSET MANAGEMENT, INC.


                              By:  /s/ Peter A. Lusk                        
                                   Peter A. Lusk
                                   Executive Vice President
                                   and Chief Operating Officer

                              STAMFORD ADVISERS CORP.


                              By:  /s/ Peter A. Lusk                       
                                   Peter A. Lusk
                                   Vice President/Secretary