Exhibit 10.4 (a)
                               FIRST AMENDMENT

          FIRST AMENDMENT (this "Amendment"), dated as of  May
20, 1998, among MCMS, Inc. (the "Borrower"), the lending
institutions party to the Credit Agreement referred to below
(each a "Bank" and, collectively, the "Banks"), and Bankers Trust
Company, as Agent (the "Agent").  All capitalized terms used
herein and not otherwise defined herein shall have the respective
meanings provided such terms in the Credit Agreement.

                              W I T N E S S E T H :

          WHEREAS, the Borrower, the Banks and the Agent are
party to a Credit Agreement, dated as of February 26, 1998 (the
"Credit Agreement"); and

          WHEREAS, the Borrower has requested that the Banks
provide the amendment provided for herein and the Banks have
agreed to provide such amendment on the terms and conditions set
forth herein;

          NOW, THEREFORE, it is agreed:

          1.  Section 8.09 of the Credit Agreement is hereby
amended by deleting the first six lines of the table therein and
inserting in lieu thereof the following:


      Fiscal Quarter                
      Ending on or about            Amount

      May 31, 1998                  $30,100,000

      August 31, 1998               $23,900,000

      November 30, 1998             $20,500,000

      February 28, 1999             $20,500,000

      May 31, 1999                  $24,000,000

      August 31, 1999               $28,500,000
          

                                        23

<PAGE>
          2.  Section 8.10 of the Credit Agreement is hereby
amended by deleting the first six lines of the table therein and
inserting in lieu thereof the following:

      Fiscal Quarter                
      Ending on or about            Ratio

      May 31, 1998                  1.6:1.0

      August 31, 1998               1.2:1.0

      Fiscal Quarter
      Ending on or about            Ratio

      November 30, 1998             1.0:1.0

      February 28, 1999             1.0:1.0

      May 31, 1999                  1.2:1.0

      August 31, 1999               1.5:1.0
          
          
          3. Section 8.11 of the Credit Agreement is hereby
amended by deleting the first three paragraphs of the table
therein and inserting in lieu thereof the following:

          Period                              Ratio
                                      
          The Effective Date to but   
          not including the last day  
          of the Borrower's fiscal    
          quarter ending on or about  
          May 31, 1998                        6.2:1.0
                                      
          Thereafter to but not       
          including the last day of   
          the Borrower's fiscal       
          quarter ending on or about  
          August 31, 1998                     8.0:1:0
                                      
          Thereafter to but not       
          including the last day of   
          the Borrower's fiscal       
          quarter ending on or about  
          November 30, 1998                   8.9:1.0
                                      
          Thereafter to but not       
          including the last day of   
          the Borrower's fiscal       
          quarter ending on or about  
          February 28, 1999                   9.2:1.0
                                      
          Thereafter to but not       
          including the last day of   
          the Borrower's fiscal       
          quarter ending on or about         
          May 31, 1999                       7.8:1.0
          
                                        24                                      

<PAGE>
                                      
          Period                              Ratio
                                      
          Thereafter to but           
          not including the           
          last day of the             
          Borrower's fiscal           
          quarter ending on or        
          about August 31,
          1999                               6.5:1.0
          
                                      
                                      
          4.  In order to induce the Banks to enter into this
Amendment, the Borrower hereby represents and warrants that (i)
no Default or Event of Default exists as of the Amendment
Effective Date (as defined below) after giving effect to this
Amendment and (ii)  on the Amendment Effective Date, both before
and after giving effect to this Amendment, all representations
and warranties contained in the Credit Agreement or in the other
Credit Documents are true and correct in all material respects.

          5.  This Amendment shall become effective on the date
(the "Amendment Effective Date") when each of the Borrower and
the Required Banks shall have signed a counterpart hereof
(whether the same or different counterparts) and shall have
delivered (including by way of facsimile transmission) the same
to the Agent at its Notice Office.

          6.  This Amendment is limited as specified and shall
not constitute a modification, acceptance or waiver of any other
provision of the Credit Agreement or any other Credit Document.

          7.  This Amendment may be executed in any number of
counterparts and by the different parties hereto on separate
counterparts, each of which counterparts when executed and
delivered shall be an original, but all of which shall together
constitute one and the same instrument.  A complete set of
counterparts shall be lodged with the Borrower and the Agent.

          8.   THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES HEREUNDER SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

                               * * *

                                        25


<PAGE>

          IN WITNESS WHEREOF, each of the parties hereto has
caused a counterpart of this Amendment to be duly executed and
delivered as of the date hereof.

                                
                                MCMS, INC.
                                   
                                By: /s/ Robert F. Subia
                                Title:President
                                   
                                
                                BANKERS TRUST COMPANY,
                                   Individually and as Agent
                                
                                By: /s/ Anthony LoGrippo
                                Title:Vice President
                                   

                                SANWA BUSINESS CREDIT CORPORATION
                                   
                                By: /s/ Peter L. Skavia
                                     Title: Vice President
                                
                                
                                FLEET NATIONAL BANK
                                
                                By: /s/ Frank H. Benesh
                                     Title: Vice President
                                
                                
                                STATE STREET BANK AND TRUST
                                COMPANY
                                
                                By: /s/ Mark H. Trachy
                                     Title: Vice President
                                

                                        26

<PAGE>

                                MERRILL LYNCH BUSINESS FINANCIAL
                                SERVICES, INC.
                                
                                By: /s/ Gary Stewart
                                     Title: Vice President
                                
                                
                                SILICON VALLEY BANK
                                
                                By: /s/ Ron Sherman
                                     Title: Vice President
                                

                                        27