
<PAGE>
                                                                    Exhibit 10.8
                                                                    ------------

                            STOCK PURCHASE AGREEMENT


Stock Purchase Agreement ("the Agreement") dated as of October 13, 1998 by and
between ACT Manufacturing, Inc. a Massachusetts corporation (the "Purchaser")
and Advanced Component Technologies Limited, a corporation registered under the
laws of Ireland ("the Company").

NOW, THEREFORE, in consideration of the mutual covenants herein contained and
for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged by the parties hereto, the Purchaser and the Company,
intending to be legally bound hereby, agree as follows:

1.   The Purchaser hereby agrees to purchase and the Company hereby agrees to
     issue and allot to the Purchaser Six Million (6,000,000) ordinary shares,
     IR(pound)0.10 each, of the Seller ("the Shares").

2.   As full payment for the Shares, the Purchaser hereby surrenders its right
     to repayment of IR(pound)600,000 of the intercompany debt between the
     Purchaser and the Company.

3.   The Company agrees to issue the Shares to the Purchaser and register the
     Shares in the name of the Purchaser.

4.   Each of the parties hereto covenants and agrees upon the request of the
     other, to do, execute, acknowledge and deliver or cause to be done,
     executed, acknowledged and delivered all such further acts, deeds,
     documents, powers of attorney and assurances as may be reasonably necessary
     or desirable to give full effect to this Agreement.

5.   This Agreement shall inure to the benefit of and be binding upon the
     parties hereto and their respective successors and assigns.

6.   This Agreement shall be construed and interpreted according to the laws of
     the Commonwealth of Massachusetts without regard to its principles of
     conflicts of laws.

7.   This Agreement may be executed in any number of counterparts, each of which
     shall be deemed an original, but all of which together shall constitute one
     agreement.

IN WITNESS WHEREOF, this Agreement has been executed by the parties hereto as of
the day and year first above written.
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ACT MANUFACTURING, INC.



By: /s/ John A. Pino
   ----------------------
   Name:  John A. Pino
   Title: President and Chief Executive Officer





ADVANCED COMPONENT
TECHNOLOGIES LIMITED



By: /s/ Aubrey Nuzem 
   ----------------------
   Name:
   Title:
