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                                                                   Exhibit 10.64

                   FIFTH AMENDMENT AND MODIFICATION AGREEMENT


         FIFTH AMENDMENT AND MODIFICATION AGREEMENT dated as of November 23,
1999 (this "Amendment") by and among HADCO CORPORATION, a Massachusetts
corporation (the "Borrower"); the direct and indirect subsidiaries of the
Borrower listed on the signature pages hereto (collectively, the "Guarantors");
BANKBOSTON, N.A., AS AGENT (the "Agent") and BANKBOSTON, N.A., individually, and
the other lending institutions (collectively, the "Banks") listed on SCHEDULE 1
to the Amended and Restated Revolving Credit Agreement dated as of December 8,
1997 (as amended and in effect from time to time, the "Credit Agreement") among
the Borrower, the Banks and the Agent. Terms not otherwise defined herein which
are defined in the Credit Agreement shall have the respective meanings assigned
to such terms in the Credit Agreement, as amended hereby.

         WHEREAS, the Borrower has requested that the Agent and the Banks amend
certain provisions of the Credit Agreement; and

         WHEREAS, upon the terms and subject to the conditions contained herein,
the Agent and the Banks are willing to amend such provisions of the Credit
Agreement;

         NOW, THEREFORE, in consideration of the mutual agreements contained in
the Credit Agreement, the other Loan Documents and this Amendment and for other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto hereby agree as follows:

         SS.1. AMENDMENT OF SS.1.1 OF THE CREDIT AGREEMENT. Section 1.1 of the
Credit Agreement is hereby amended by:

                  (a) inserting the following new definitions in the proper
alphabetical order:

                  "FIFTH AMENDMENT EFFECTIVE DATE. The "Effective Date", as
         defined in the Fifth Amendment and Modification Agreement dated as of
         November 23, 1999 among the Borrower, the Guarantors, the Agent and the
         Banks."

                  "SECTION 9.5.2 SUBSIDIARY. Any Subsidiary acquired pursuant to
         Section 9.5.2 that is organized under the laws of a jurisdiction other
         than the United States of America and the States (or the District of
         Columbia) thereof."

                  (b) deleting the definition of "Guarantors" in its entirety
         and substituting in lieu thereof the following new definition:


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                  "GUARANTORS. (i) Hadco Santa Clara, Hadco Phoenix, CCIR of
         Texas, and, until the completion of the Restructuring Transaction, CCIR
         of California; and (ii) any other direct or indirect Subsidiary of the
         Borrower (other than Hadco FSC, New Zycon, Hadco Scotland, Hadco
         Ireland, Hadco Malaysia, Hadco Singapore, New Continental, CCIR
         International and any Section 9.5.2 Subsidiary)."

         SS.2. AMENDMENT OF SS.9.1(i) OF THE CREDIT AGREEMENT. Section 9.1(i) of
the Credit Agreement is hereby deleted in its entirety and the following new
ss.9.1(i) is hereby substituted in lieu thereof:

                  "(i) Indebtedness of (i) a Guarantor, following its execution
         and delivery of its Guaranty to the Agent, to the Borrower; (ii) Hadco
         FSC to the Borrower in an aggregate amount not to exceed $2,000,000;
         (iii) Hadco Malaysia and the Section 9.5.2 Subsidiaries to the Borrower
         in an aggregate amount for all such entities not to exceed $65,000,000,
         PROVIDED, HOWEVER, that no more than $25,000,000 may be incurred by
         Hadco Malaysia in any one fiscal year of the Borrower and if during any
         such fiscal year the amount of such Indebtedness permitted to be
         incurred by Hadco Malaysia is not so utilized, such unutilized amount
         may be utilized in the next succeeding fiscal year; PROVIDED, FURTHER,
         that no more than $15,000,000 in the aggregate may be incurred by the
         Section 9.5.2 Subsidiaries and any such Indebtedness shall be evidenced
         by a duly executed promissory note (A) issued by such Section 9.5.2
         Subsidiary to the Borrower and (B) duly endorsed to the Agent pursuant
         to the Security Agreement; (iv) New Zycon or New Continental to the
         Borrower in an aggregate amount, for each such company, not to exceed
         $50,000; (v) CCIR International to the Borrower in an aggregate amount
         not to exceed $2,000,000; and (vi) Hadco Scotland, Hadco Singapore
         and/or Hadco Ireland to the Borrower in an aggregate amount for all
         such entities not to exceed $5,000,000;".

         SS.3. AMENDMENT OF SS.9.5.2 OF THE CREDIT AGREEMENT. Section 9.5.2 of
the Credit Agreement is hereby deleted in its entirety and the following new
ss.9.5.2 is hereby substituted in lieu thereof:

                  "9.5.2 ACQUISITIONS. The Borrower will not, and will not
         permit any of the other Transaction Parties to agree to or effect any
         asset acquisition or stock acquisition (other than the acquisition of
         assets in the ordinary course of business consistent with past
         practices); PROVIDED, HOWEVER, that so long as no Default or Event of
         Default has occurred and is continuing or would result therefrom, the
         Borrower may make one or more asset or stock acquisitions in an amount
         not to exceed $30,000,000 in the aggregate; PROVIDED, HOWEVER, that (i)
         the business to be acquired (the "Target") is in the same or similar
         lines of business as the Borrower and the other Transaction Parties,
         (ii) after giving effect to such Permitted Acquisition, and assuming
         full funding of such Permitted Acquisition


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         on the initial Drawdown Date of the sole or initial Loan, the proceeds
         of which are to be used to fund all or any portion of such Permitted
         Acquisition, the ratio of Consolidated Funded Debt as at the most
         recent fiscal quarter end of the Borrower to EBITDA for the four
         consecutive fiscal quarters of the Borrower ending with such quarter
         end (as shown on a PRO FORMA basis based upon (A) the most recently
         delivered financial statements of the Borrower and its Subsidiaries
         delivered in accordance with ss.8.4 and (B) audited financial
         statements for such Target as at the most recent fiscal quarter end of
         the Borrower which are accompanied by an unqualified audited opinion
         letter from Arthur Anderson LLP or another nationally recognized
         accounting firm satisfactory to the Agent and the Majority Banks or
         which are otherwise satisfactory to the Agent and the Majority Banks)
         would not exceed 3.25:1.0; and (iii) contemporaneously with the closing
         of such Permitted Acquisition, the Borrower shall provide to the Agent
         and the Banks a compliance certificate in the form of EXHIBIT C, duly
         certified by the principal financial or accounting officer of the
         Borrower, indicating the Borrower's compliance with (x) the financial
         covenants contained in ss.10 immediately prior to and, on A Pro FORma
         basis, immediately following such Permitted Acquisition and (y) on a
         PRO FORMA basis, the requirement set forth in ss.9.5.2(ii); anD
         PROVIDED FURTHER that, contemporaneously with the closing of such
         Permitted Acquisition, the Borrower shall (i) take such action as may
         be necessary or advisable in the opinion of the Agent to pledge or
         cause to be pledged to the Agent, for the benefit of the Banks and the
         Agent, on a perfected, first-priority basis all of the capital stock or
         other equity interests of such Subsidiary (except that 65% (or such
         larger percentage as may be permitted without creating material adverse
         tax consequences for the Borrower under the Code) of the capital stock
         of such Subsidiary that is organized under the laws of a jurisdiction
         other than the United States of America and the States (or the District
         of Columbia) thereof shall be pledged) pursuant to a pledge agreement
         in form and substance satisfactory to the Agent, which such pledge
         agreement shall be a Stock Pledge Agreement and a Security Document
         hereunder, (ii) cause any such Subsidiary which is or is to become a
         Guarantor to guaranty all of the Obligations hereunder pursuant to a
         Guaranty in the form of EXHIBIT E, which Guaranty shall be a Guaranty
         and Security Document hereunder, (iii) cause any such Subsidiary which
         is or is to become a Guarantor to take all steps as may be necessary or
         advisable in the opinion of the Agent to grant to the Agent, for the
         benefit of the Banks and the Agent, a first priority, perfected
         security interest in substantially all of its assets as collateral
         security for such guaranty, pursuant to security documents, mortgages,
         pledges and other documents in form and substance satisfactory to the
         Agent, each of which documents shall be Security Documents hereunder;
         and (iv) deliver to the Agent all such evidence of corporate
         authorization, legal opinions (including local counsel opinions where
         applicable), and other documentation as


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         the Agent may request. To the extent that any such Permitted
         Acquisition alters the accuracy or completeness of any of the Schedules
         hereto, the Borrower shall deliver to the Agent, contemporaneously with
         the delivery of the loan documentation referred to above, revised
         schedules reflecting changes resulting from such Permitted Acquisition;
         PROVIDED that the Agent shall only be required to accept such revised
         schedules, and such revised schedules shall only become part of this
         Credit Agreement, in the event that the Borrower shall have taken any
         and all action necessary to bring such newly acquired Subsidiary into
         compliance with each representation and warranty set forth herein,
         including in ss.7 hereof; and PROVIDED FURTHER that no change resulting
         from any Permitted Acquisition would have a material adverse effect on
         the Borrower and the other Transaction Parties, taken as a whole."

         Ss.4. AMENDMENT OF SS.9.10 OF THE CREDIT AGREEMENT. Section 9.10 of the
Credit Agreement is hereby amended by deleting the last sentence thereof in its
entirety and substituting in lieu thereof the following:

                  "Neither the Borrower nor any of the other Transaction Parties
         shall (a) without limiting the Indebtedness and Investment limitations
         set forth in ss.ss.9.1(i), 9.3(f) and 9.3(g), transfer assets to Hadco
         Scotland, Hadco Ireland, Hadco Singapore (following the incorporation
         thereof), Hadco Malaysia or any Section 9.5.2 Subsidiary in an
         aggregate amount exceeding, for all such entities, $2,000,000 or (b)
         permit Hadco Scotland, Hadco Ireland, Hadco Singapore (following the
         incorporation thereof), Hadco Malaysia or any Section 9.5.2 Subsidiary
         at any one time to own, hold or have an interest in, property or
         assets, whether tangible or intangible and including cash and cash
         equivalents, in excess of those reasonably required for the conduct of
         each such entity's business operations in the ordinary course."

         SS.5. CONDITIONS TO EFFECTIVENESS. This Amendment shall be deemed to be
effective as of the date first written above (the "Effective Date") upon the
Agent's receipt of the following, each in form and substance satisfactory to the
Agent:

                  (a) facsimile copies of original counterparts (to be followed
         promptly by original counterparts) or original counterparts of this
         Amendment, duly executed by each of the Borrower, the Guarantors, the
         Agent and the Majority Banks;

                  (b) each of the Borrower and the Guarantors shall have
         certified (a) that its charter or other incorporation documents and
         by-laws have not been amended since the date such charter or other
         incorporation documents and by-laws were certified to the Agent (or
         shall deliver the same if amended), (b) that it is in good standing or
         is authorized to do business in its state of incorporation and in each


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         state in which it does business, (c) resolutions of its Board of
         Directors authorizing this Amendment and the transactions contemplated
         hereby, and (d) that its Perfection Certificate is true and correct in
         all material respects as of the date hereof (or shall deliver an
         amended and restated Perfection Certificate);

                  (c) such other documents, agreements and items as the Agent
         may require.

         SS.6. REPRESENTATIONS AND WARRANTIES; NO DEFAULT; AUTHORIZATION. Each
of the Borrower and the Guarantors hereby represents and warrants to each of the
Agent and the Banks as follows:

                  (a) Each of the representations and warranties of the Borrower
         and the Guarantors contained in the Credit Agreement, the other Loan
         Documents or in any document or instrument delivered pursuant to or in
         connection with the Credit Agreement, the other Loan Documents or this
         Amendment was true as of the date as of which it was made and is true
         as of the Effective Date (except to the extent of changes resulting
         from transactions contemplated or permitted by the Credit Agreement, as
         amended hereby, and the other Loan Documents and changes occurring in
         the ordinary course of business that singly or in the aggregate are not
         materially adverse and to the extent that such representations and
         warranties relate expressly to an earlier date), and no Default or
         Event of Default has occurred and is continuing as of the date of this
         Amendment or would occur after giving effect to the transactions
         contemplated by this Amendment; and

                  (b) This Amendment has been duly authorized, executed and
         delivered by the Borrower and each of the Guarantors, and shall be in
         full force and effect upon the satisfaction of the conditions set forth
         in ss.5 hereof, and the agreements of the Borrower and each of the
         Guarantors contained herein, in the Credit Agreement as herein amended,
         or in the other Loan Documents respectively, constitute the legal,
         valid and binding obligations of the Borrower and each of the
         Guarantors party hereto or thereto, enforceable against the Borrower or
         such Guarantor, in accordance with their respective terms, except as
         enforceability is limited by bankruptcy, insolvency, reorganization,
         moratorium or other laws relating to or affecting generally the
         enforcement of creditors' rights and except to the extent that
         availability of the remedy of specific performance or injunctive relief
         is subject to the discretion of the court before which any proceeding
         therefor may be brought.

         SS.7. RATIFICATION, ETC. Except as expressly amended hereby, the Credit
Agreement, the other Loan Documents and all documents, instruments and
agreements related thereto are hereby ratified and confirmed in all respects and
shall continue in full force and effect. All


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references in the Credit Agreement or such other Loan Documents or in any
related agreement or instrument to the Credit Agreement or such other Loan
Documents shall hereafter refer to such agreements as amended hereby, pursuant
to the provisions of the Credit Agreement.

         SS.8. NO PRESENT CLAIMS. In order to eliminate any possibility that any
past conditions, acts, omissions, events, circumstances or matters would impair
or otherwise adversely affect any of the rights, interests, contracts,
collateral security or remedies of the Agent or any of the Banks, each of the
Borrower and the Guarantors hereby acknowledges and agrees that: (i) neither it
nor any of the other Transaction Parties has any claim or cause of action
against the Agent, any of the Banks or any of their directors, officers,
employees or agents; (ii) neither it nor any of the other Transaction Parties
has any offset right, counterclaim or defense of any kind against any of its
obligations, indebtedness or liabilities to the Agent and/or the Banks,
including, without limitation, the Obligations; and (iii) each of the Agent and
the Banks has heretofore properly performed and satisfied in a timely manner all
of its obligations to each of the Borrower and the other Transaction Parties.

         SS.9. EXPENSES. Without limiting the expense reimbursement requirements
set forth in ss.16 of the Credit Agreement, the Borrower agrees to pay on demand
all costs and expenses, including reasonable attorneys' fees, of the Agent
incurred in connection with this Amendment.

         SS.10. NO IMPLIED WAIVER, ETC. Except as expressly provided herein,
nothing contained herein shall constitute a waiver of, impair or otherwise
affect any of the Obligations, any other obligations of the Borrower or any of
the Transaction Parties or any right of the Agent or the Banks consequent
thereon. The waivers and consents provided herein are limited strictly to their
terms. Neither the Agent nor any of the Banks shall have any obligation to issue
any further waiver or consent with respect to the subject matter hereof or any
other matter.

         SS.11. COUNTERPARTS. This Amendment may be executed in one or more
counterparts, each of which shall be deemed an original but which together shall
constitute one and the same instrument.

         SS.12. GOVERNING LAW. THIS AMENDMENT SHALL FOR ALL PURPOSES BE GOVERNED
BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF
MASSACHUSETTS (WITHOUT REFERENCE TO CHOICE OR CONFLICTS OF LAWS).



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         IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
a document under seal as of the date first above written.


                                        HADCO CORPORATION



                                        By:  /s/ F. Gordon Bitter
                                             -----------------------------------
                                             Name: F. Gordon Bitter
                                             Title: CFO/Treasurer, Sr. Vice
                                                    President

                                        BANKBOSTON, N.A., individually and
                                        as Agent



                                        By:  /s/ Sharon A. Stone
                                             -----------------------------------
                                             Name: Sharon A. Stone
                                             Title:  Director

                                        BANK OF AMERICA, N.A.



                                        By:  /s/ Robert Kosche
                                             -----------------------------------
                                             Name: Robert Kosche
                                             Title: Vice President


                                        ABN AMRO BANK N.V.



By:  /s/ James S. Adelsheim             By:  /s/ John D. Rogers
     -------------------------------         -----------------------------------
     Name: James S. Adelsheim                Name: John D. Rogers
     Title: Group Vice President             Title: Vice President

                                        BANK ONE, N.A. (f/k/a The First
                                        National Bank Of Chicago)



                                        By:  /s/ Stephen E. McDonald
                                             -----------------------------------
                                             Name: Stephen E. McDonald
                                             Title: Senior Vice President


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                                      -8-

                                        KEYBANK NATIONAL ASSOCIATION.



                                        By:  /s/ Francis Lotz
                                             -----------------------------------
                                             Name: Francis Lotz
                                             Title: Portfolio Officer

                                        THE BANK OF NOVA SCOTIA



                                        By:  /s/ T.M. Pitcher
                                             -----------------------------------
                                             Name: T.M. Pitcher
                                             Title: Authorized Signatory

                                        MORGAN GUARANTY TRUST
                                        COMPANY OF NEW YORK



                                        By:  /s/ Francoise Berthelot
                                             -----------------------------------
                                             Name: Francoise Berthelot
                                             Title: Vice President


                                        SUNTRUST BANK, ATLANTA



                                        By:  /s/ W. David Wisdom
                                             -----------------------------------
                                             Name: W. David Wisdom
                                             Title: Vice President

                                        CITIZENS BANK OF MASSACHUSETTS



                                        By:  /s/ Bruce S. Daniels
                                             -----------------------------------
                                             Name: Bruce S. Daniels
                                             Title: V.P.

                                        USTRUST



                                        By:  Eastman, D.G.
                                             -----------------------------------
                                             Name: Eastman, D.G.
                                             Title: Vice President


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                                        FLEET BANK-NH



                                        By:  /s/ Marcia Clatorre
                                             -----------------------------------
                                             Name: Marcia Clatorre
                                             Title: Vice President

                                        FIRST UNION NATIONAL BANK,
                                        successor by merger to CORESTATES
                                        BANK, N.A.



                                        By:  /s/ Robert A. Brown
                                             -----------------------------------
                                             Name: Robert A. Brown
                                             Title: Vice President

                                        MELLON BANK, N.A.



                                        By:  /s/ R. Jane Westrich
                                             -----------------------------------
                                             Name: R. Jane Westrich
                                             Title: Vice President

                                        CITIZENS BANK NEW HAMPSHIRE



                                        By:  /s/ Lori A. Chandonnais
                                             -----------------------------------
                                             Name: Lori A. Chandonnais
                                             Title: Vice President




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Each of the undersigned hereby acknowledges the foregoing Amendment as of the
Effective Date and agrees that its obligations under the Guaranty to which it is
a party will extend to the Agreement, as so amended, and the other Loan
Documents, as so amended.


                                        HADCO SANTA CLARA, INC.



                                        By:  /s/ F. Gordon Bitter
                                             -----------------------------------
                                             Title: Treasurer


                                        HADCO PHOENIX, INC.


                                        By:  /s/ F. Gordon Bitter
                                             -----------------------------------
                                             Title: Treasurer


                                        CCIR OF CALIFORNIA CORP.


                                        By:  /s/ F. Gordon Bitter
                                             -----------------------------------
                                             Title: Treasurer


                                        CCIR OF TEXAS CORP.


                                        By:  /s/ F. Gordon Bitter
                                             -----------------------------------
                                             Title: Treasurer