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                                                                   EXHIBIT 10.66





                                 TRUST AGREEMENT

                                     BETWEEN

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                                HADCO CORPORATION

                                       AND

                        FIDELITY MANAGEMENT TRUST COMPANY

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                       HADCO CORPORATION RETIREMENT TRUST








                            DATED AS OF JUNE 1, 1996


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                                TABLE OF CONTENTS

SECTION                                                                  PAGE
-------                                                                  ----

1        Trust........................................................
2        Exclusive Benefit and Reversion of Sponsor Contributions.....
3        Disbursements................................................
         (a)  Administrator Directed Disbursements
         (b)  Participant Withdrawal Requests
         (c)  Limitations

4        Investment of Trust..........................................
         (a)  Selection of Investment Options
         (b)  Available Investment Options
         (c)  Participant Direction
         (d)  Mutual Funds
         (e)  Notes
         (f)  Guaranteed Investment Contracts
         (g)  Participation in Commingled Pools
         (h)  Reliance of Trustee on Directions
         (i)  Trustee Powers

5        Recordkeeping and Administrative Services to Be Performed....
         (a)  General
         (b)  Accounts
         (c)  Inspection and Audit
         (d)  Effect of Plan Amendment
         (e)  Returns, Reports and Information

6        Compensation and Expenses....................................

7        Directions and Indemnification...............................
         (a)  Identity of Administrator and Investment Committee
         (b)  Directions from Administrator
         (c)  Directions from Investment Committee
         (d)  Co-Fiduciary Liability
         (e)  Indemnification
         (f)  Survival

8        Resignation or Removal of Trustee............................
         (a)  Resignation
         (b)  Removal



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9        Successor Trustee............................................
         (a)  Appointment
         (b)  Acceptance
         (c)  Corporate Action

10       Termination..................................................

11       Resignation, Removal, and Termination Notices................

12       Duration.....................................................

13       Amendment or Modification....................................

14       General......................................................
         (a)  Performance by Trustee, its Agents or Affiliates
         (b)  Entire Agreement
         (c)  Waiver
         (d)  Successors and Assigns
         (e)  Partial Invalidity
         (f)  Section Headings

15       Governing Law................................................
         (a)  Massachusetts Law Controls
         (b)  Trust Agreement Controls

SCHEDULES

A.       Recordkeeping and Administrative Services
B.       Fee Schedule
C.       Investment Options
D.       Administrator's Authorization Letter
E.       Investment Committee's Authorization Letter
F.       IRS Determination Letter or Opinion of Counsel
G.       Telephone Exchange Guidelines




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         TRUST AGREEMENT, dated as of the first day of June, 1996, between HADCO
CORPORATION, a Massachusetts corporation, having an office at 12A Manor Parkway,
Salem, New Hampshire 03079 (the "SPONSOR"), and FIDELITY MANAGEMENT TRUST
COMPANY, a Massachusetts trust company, having an office at 82 Devonshire
Street, Boston, Massachusetts 02109 (the "TRUSTEE").

                                   WITNESSETH:

         WHEREAS, the Sponsor is the sponsor of the HADCO Corporation Retirement
Plan (the "PLAN"); and

         WHEREAS, the Sponsor wishes to establish a trust to hold and invest
plan assets under the Plan for the exclusive benefit of participants in the Plan
and their beneficiaries; and

         WHEREAS, the HADCO Corporation Retirement Plan Investment Committee
(the "INVESTMENT COMMITTEE") is the named fiduciary of the Plan (within the
meaning of section 402(a) of the Employee Retirement Income Security Act of
1974, as amended ("ERISA")); and

         WHEREAS, the Trustee is willing to hold and invest the aforesaid plan
assets in trust pursuant to the provisions of this Trust Agreement, which shall
constitute a continuation, by means of an amendment and restatement, of each of
the prior trusts from which plan assets are transferred to the Trustee; and

         WHEREAS, the Trustee is willing to hold and invest the aforesaid plan
assets in trust among several investment options selected by the Investment
Committee; and

         WHEREAS, the Sponsor wishes to have the Trustee perform certain
ministerial recordkeeping and administrative functions under the Plan; and




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         WHEREAS, the HADCO Corporation Retirement Plan Administrative Committee
(the "ADMINISTRATOR") is the administrator of the Plan (within the meaning of
section 3(16)(A) of ERISA); and

         WHEREAS, the Trustee is willing to perform recordkeeping and
administrative services for the Plan if the services are purely ministerial in
nature and are provided within a framework of plan provisions, guidelines and
interpretations conveyed in writing to the Trustee by the Administrator.

         NOW, THEREFORE, in consideration of the foregoing premises and the
mutual covenants and agreements set forth below, the Sponsor and the Trustee
agree as follows:

         Section 1. TRUST. The Sponsor hereby establishes the HADCO Corporation
Retirement Trust (the "TRUST") with the Trustee. The Trust shall consist of an
initial contribution of money or other property acceptable to the Trustee in its
sole discretion, made by the Sponsor or transferred from a previous trustee
under the Plan, such additional sums of money as shall from time to time be
delivered to the Trustee under the Plan, all investments made therewith and
proceeds thereof, and all earnings and profits thereon, less the payments that
are made by the Trustee as provided herein, without distinction between
principal and income. The Trustee hereby accepts the Trust on the terms and
conditions set forth in this Agreement. In accepting this Trust, the Trustee
shall be accountable for the assets received by it, subject to the terms and
conditions of this Agreement.

         Section 2. EXCLUSIVE BENEFIT AND REVERSION OF SPONSOR CONTRIBUTIONS.
Except as provided under applicable law, no part of the Trust may be used for,
or diverted to, purposes other than the exclusive benefit of the participants in
the Plan or their beneficiaries prior to the satisfaction of all liabilities
with respect to the participants and their beneficiaries.



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                                      -3-


         Section 3.  DISBURSEMENT.

                  (a) ADMINISTRATOR DIRECTED DISBURSEMENTS. The Trustee shall
make disbursements in the amounts and in the manner that the Administrator
directs from time to time in writing. The Trustee shall have no responsibility
to ascertain such direction's compliance with the terms of the Plan or of any
applicable law or the direction's effect for tax purposes or otherwise; nor
shall the Trustee have any responsibility to see to the application of any
disbursement.

                  (b) PARTICIPANT WITHDRAWAL REQUESTS. The Sponsor hereby
directs that, pursuant to the Plan, a participant withdrawal request (in-service
or full withdrawal) may be made by the participant by telephone, and the Trustee
shall process such request only after the identity of the participant is
verified by use of a personal identification number ("PIN") and social security
number. The Trustee shall process such withdrawal in accordance with written
guidelines provided by the Sponsor and documented in the Plan Administrative
Manual.

                  (c) LIMITATIONS. The Trustee shall not be required to make any
disbursement in excess of the net realizable value of the assets of the Trust at
the time of the disbursement. The Trustee shall not be required to make any
disbursement in cash unless the Administrator has provided a written direction
as to the assets to be converted to cash for the purpose of making the
disbursement.

         Section 4.  INVESTMENT OF TRUST.

                  (a) SELECTION OF INVESTMENT OPTIONS. The Trustee shall have no
responsibility for the selection of investment options under the Trust and shall
not render investment advice to any person in connection with the selection of
such options.




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                  (b) AVAILABLE INVESTMENT OPTIONS. The Investment Committee
shall direct the Trustee as to the investment options: (i) in which the Trust
shall be invested during the participant recordkeeping reconciliation period,
which shall be defined as the period beginning on the date of the initial
transfer of assets to the Trustee and ending on the date of the completion of
the reconciliation of participant records, (ii) in which investment option any
portion of participant's accounts that are not directed by participants are to
be invested, and (iii) in which Plan participants may invest, subject to the
following limitations. The Investment Committee may determine to offer as
investment options only (i) securities issued by the investment companies
advised by Fidelity Management & Research Company ("Mutual Funds"), (ii) equity
securities issued by the Sponsor or an affiliate which are publicly-traded and
which are "qualifying employer securities" within the meaning of section
407(d)(5) of ERISA ("SPONSOR STOCK"), (iii) notes evidencing loans to Plan
participants in accordance with the terms of the Plan, (iv) guaranteed
investment contracts chosen by the Trustee, and (v) collective investment funds
maintained by the Trustee for qualified plans; provided that the Trustee shall
be considered a fiduciary with investment discretion only with respect to Plan
assets that are invested in guaranteed investment contracts chosen by the
Trustee or in collective investment funds maintained by the Trustee for
qualified plans. The investment options initially selected by the Investment
Committee are identified on Schedules "A" and "C" attached hereto. The
Investment Committee may add additional investment options with the consent of
the Trustee and upon mutual amendment of this Trust Agreement and the Schedules
thereto to reflect such additions.

                  (c) PARTICIPANT DIRECTION. Each Plan participant may direct
the Trustee in which investment option(s) to invest the assets in the
participant's individual accounts. Such directions may be made by Plan
participants by use of the telephone exchange system maintained





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for such purposes by the Trustee or its agent, in accordance with written
Telephone Exchange Guidelines attached hereto as Schedule "G". In the event that
the Trustee fails to receive a proper direction, the assets shall be invested in
the investment option set forth for such purpose on Schedule "C", until the
Trustee receives a proper direction.

                  (d) MUTUAL FUNDS. The Sponsor hereby acknowledges that it has
received from the Trustee a copy of the prospectus for each Mutual Fund selected
by the Investment Committee as a Plan investment option or short-term investment
fund. Trust investments in Mutual Funds shall be subject to the following
limitations:

                           (i) EXECUTION OF PURCHASES AND SALES. Purchases and
         sales of Mutual Funds (other than for exchanges) shall be made on the
         date on which the Trustee receives from the Sponsor in good order all
         information and documentation necessary to accurately effect such
         purchases and sales (or in the case of a purchase, the subsequent date
         on which the Trustee has received a wire transfer of funds necessary to
         make such purchase). Exchanges of Mutual Funds shall be made in
         accordance with the Telephone Exchange Guidelines attached hereto as
         Schedule "G".

                           (ii) VOTING. Each Plan participant shall have the
         right to direct the Trustee as to the manner in which the Trustee is to
         vote the shares of any Mutual Funds credited to the participant's
         accounts (both vested and unvested). At the time of mailing of notice
         of each annual or special stockholders' meeting of any Mutual Fund, the
         Trustee shall send a copy of the notice and all proxy solicitation
         materials to each Plan participant who has shares of the Mutual Fund
         credited to the participants accounts, together with a voting direction
         form for return to the Trustee or its designee, and the Trustee shall
         vote the shares as directed by the participant. The Investment
         Committee shall receive a copy




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                                      -6-


         of the notice and all proxy solicitation materials for shares of the
         Mutual Fund held in any short-term investment fund or liquidity
         reserve. The Investment Committee shall have the right to direct the
         Trustee as to the manner in which the Trustee is to vote the Mutual
         Fund shares held in any short-term investment fund or liquidity
         reserve, and the Trustee shall vote such shares as directed by the
         Investment Committee. The Trustee shall not vote shares for which it
         has received no directions from the participant or the Investment
         Committee. During the participant recordkeeping reconciliation period,
         the Investment Committee shall have the right to direct the Trustee as
         to the manner in which the Trustee is to vote the shares of the Mutual
         Funds in the Trust including Mutual Fund shares held in any short-term
         investment fund for liquidity reserve. With respect to all rights other
         than the right to vote, the Trustee shall follow the directions of the
         participant and if no such directions are received, the directions of
         the Investment Committee. The Trustee shall have no further duty to
         solicit directions from participants or the Sponsor.

                  (e) NOTES. The Administrator shall act as the Trustee's agent
for the purpose of holding all trust investments in participant loan notes and
related documentation and as such shall: (1) hold physical custody of and keep
safe the notes and other loan documents, (ii) collect and remit all principal
and interest payments to the Trustee and (iii) keep the repayments of such loans
separate from the other assets of the Administrator and clearly identify such
assets as Plan assets and (iv) cancel and surrender the notes and other loan
documentation when a loan has been paid in full. To originate a participant
loan, the Plan participant shall direct the Trustee as to the type of loan to be
made from the participant's individual account. Such directions shall be made by
Plan participants by use of the telephone exchange system maintained for such
purpose by the Trustee or its agent. The Trustee shall determine, based on the
current value of the participant's





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account, the amount available for the loan. Based on the interest rate supplied
by the Administrator in accordance with the terms of the Plan, the Trustee shall
advise the participant of such interest rate, as well as the installment payment
amounts. The Trustee shall forward the loan document and truth-in-lending
disclosures to the participant for execution and submission for approval to the
Administrator. The Administrator shall have the responsibility for approving the
loan and instructing the Trustee to send the loan proceeds to the Administrator
or to the participant if so directed by the Administrator. In all cases, such
instruction by the Administrator shall be made within thirty (30) days of the
participant's initial request (the origination date).

                  (f) GUARANTEED INVESTMENT CONTRACTS. Trust investments in
guaranteed investment contracts ("GICs") shall be subject to the following
limitations:

                           (i) COMMINGLED POOL INVESTMENTS. To the extent that
         the Investment Committee selects as an investment option the Managed
         Income Portfolio of the Fidelity Group Trust for Employee Benefit Plans
         (the "Group Trust"), the Investment Committee hereby (A) agrees to the
         terms of the Group Trust and adopts said terms as a part of this
         Agreement and (B) acknowledges that it has received from the Trustee a
         copy of the Group Trust, the Declaration of Separate Fund for the
         Managed Income Portfolio of the Group Trust, and the Circular for the
         Managed Income Portfolio.

                           (ii) In order to provide the necessary monies for
         exchanges or redemptions from the GIC investment option, if any, under
         the Plan, the Investment Committee agrees that the Plan shall maintain
         a liquidity reserve allocated to the Plan GIC investment option in
         Fidelity Institutional Cash Portfolios: Money Market Portfolio: Class A
         or such other Mutual Fund or commingled money market pool as agreed to
         by the Investment Committee and the Trustee.

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                                      -8-


                  (g) RELIANCE OF TRUSTEE ON DIRECTIONS.

                           (i) The Trustee shall not be liable for any loss, or
         by reason of any breach, which arises from any participant's exercise
         or non-exercise of rights under this Section 4 over the assets in the
         participant's accounts.

                           (ii) The Trustee shall not be liable for any loss, or
         by reason of any breach, which arises from the Investment Committee's
         exercise or non-exercise of rights under this Section 4, unless it was
         clear on their face that the actions to be taken under the Investment
         Committee's directions were prohibited by the fiduciary duty rules of
         Section 404(a) of ERISA or were contrary to the terms of the Plan or
         this Agreement.

                  (h) TRUSTEE POWERS. The Trustee shall have the following
powers and authority:


                           (i) Subject to paragraphs (b), (c), (d) and (e) of
         this Section 4, to sell, exchange, convey, transfer, or otherwise
         dispose of any property held in the Trust, by private contract or at
         public auction. No person dealing with the Trustee shall be bound to
         see to the application of the purchase money or other property
         delivered to the Trustee or to inquire into the validity, expediency,
         or propriety of any such sale or other disposition.

                           (ii) Subject to paragraphs (b) and (c) of this
         Section 4, to invest in guaranteed investment contracts and short term
         investments (including interest bearing accounts with the Trustee or
         money market mutual funds advised by affiliates of the Trustee) and in
         collective investment funds maintained by the Trustee for qualified
         plans, in which case the provisions of each collective investment fund
         in which the Trust is invested shall be deemed adopted by the Sponsor
         and the provisions thereof incorporated



<PAGE>   12
                                      -9-


         as a part of this Trust as long as the fund remains exempt from
         taxation under Sections 401(a) and 501(a) of the Internal Revenue Code
         of 1986, as amended.

                           (iii) To cause any securities or other property held
         as part of the Trust to be registered in the Trustee's own name, in the
         name of one or more of its nominees, or in the Trustee's account with
         the Depository Trust Company of New York and to hold any investments in
         bearer form, but the books and records of the Trustee shall at all
         times show that all such investments are part of the Trust.

                           (iv) To keep that portion of the Trust in cash or
         cash balances as the Investment Committee or Administrator may, from
         time to time, deem to be in the best interest of the Trust.

                           (v) To make, execute, acknowledge, and deliver any
         and all documents of transfer or conveyance and to carry out the powers
         herein granted.

                           (vi) To borrow funds from a bank not affiliated with
         the Trustee in order to provide sufficient liquidity to process Plan
         transactions in a timely fashion, provided that the cost of borrowing
         shall be allocated in a reasonable fashion to the investment fund(s) in
         need of liquidity.

                           (vii) To settle, compromise, or submit to arbitration
         any claims, debts, or damages due to or arising from the Trust; to
         commence or defend suits or legal or administrative proceedings; to
         represent the Trust in all suits and legal and administrative hearings;
         and to pay all reasonable expenses arising from any such action, from
         the Trust if not paid by the Sponsor.

                           (viii) Subject to the prior approval of the Sponsor,
         to employ legal, accounting, clerical, and other such extraordinary
         assistance as may be required in



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                                      -10-


         carrying out the provisions of this Agreement and to pay their
         reasonable expenses and compensation from the Trust if not paid by the
         Sponsor.

                           (ix) To do all other acts although not specifically
         mentioned herein, as the Trustee may deem necessary to carry out any of
         the foregoing powers and the purposes of the Trust.

         Section 5. RECORDKEEPING AND ADMINISTRATIVE SERVICES TO BE PERFORMED.

                 (a) GENERAL. The Trustee shall perform those recordkeeping and
administrative functions described in Schedule "A" attached hereto. These
recordkeeping and administrative functions shall be performed within the
framework of the Administrator's written directions regarding the Plan's
provisions, guidelines and interpretations.

                  (b) ACCOUNTS. The Trustee shall keep accurate accounts of all
investments, receipts, disbursements, and other transactions hereunder, and
shall report the value of the assets held in tile Trust as of the last day of
each fiscal quarter of the Plan and, if not on the last day of a fiscal quarter,
the date on which the Trustee resigns or is removed as provided in Section 8 of
this Agreement or is terminated as provided in Section 10 (the "Reporting
Date"). Within thirty (30) days following each Reporting Date or within sixty
(60) days in the case of a Reporting Date caused by the resignation or removal
of the Trustee, or the termination of this Agreement, the Trustee shall file
with the Administrator a written account setting forth all investments,
receipts, disbursements, and other transactions effected by the Trustee between
the Reporting Date and the prior Reporting Date, and setting forth the value of
the Trust as of the Reporting Date. Except as otherwise required under ERISA,
upon the expiration of six (6) months from the date of filing such account with
the Administrator, the Trustee shall have no liability or further accountability
to anyone with respect to the propriety of its acts or transactions shown in
such



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                                      -11-


account, except with respect to such acts or transactions as to which the
Sponsor shall within such six (6) month period file with the Trustee written
objections.

                  (c) INSPECTION AND AUDIT. Except as required under ERISA, all
records generated by the Trustee in accordance with paragraphs (a) and (b) shall
be open to inspection and audit, during the Trustee's regular business hours
prior to the termination of this Agreement, by the Administrator or any person
designated by the Administrator. Upon the resignation or removal of the Trustee
or the termination of this Agreement, the Trustee shall provide to the
Administrator, at no expense to the Sponsor, in the format regularly provided to
the Administrator, a statement of each participant's accounts as of the
resignation, removal, or termination, and the Trustee shall provide to the
Administrator or the Plan's new recordkeeper such further records as are
reasonable, at the Sponsor's expense.

                  (d) EFFECT OF PLAN AMENDMENT. A confirmation of the current
qualified status of the Plan is attached hereto as Schedule "F". The Trustee's
provision of the recordkeeping and administrative services set forth in this
Section 5 shall be conditioned on the Sponsor delivering to the Trustee a copy
of any amendment to the Plan as soon as administratively feasible following the
amendment's adoption, with, if requested, an IRS determination letter or an
opinion of counsel substantially in the form of Schedule "F" covering such
amendment, and on the Administrator providing the Trustee on a timely basis with
all the information the Administrator deems necessary for the Trustee to perform
the recordkeeping and administrative services and such other information as the
Trustee may reasonably request.

                  (e) RETURNS, REPORTS AND INFORMATION. The Administrator shall
be responsible for the preparation and filing of all returns, reports, and
information required of the Trust or Plan by law. The Trustee shall provide the
Administrator with such information as the Administrator



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                                      -12-


may reasonably request to make these filings. The Administrator shall also be
responsible for making any disclosures to Participants required by law, except
such disclosure as may be required under federal or state truth-in-lending laws
with regard to Participant loans, which shall be provided by the Trustee.

         Section 6. COMPENSATION AND EXPENSES. Within thirty (30) days of
receipt of the Trustee's bill, which shall be computed and billed in accordance
with Schedule "B" attached thereto and made a part hereof, as amended from time
to time, the Sponsor shall send to the Trustee a payment in such amount or the
Sponsor may direct the Trustee to deduct such amount from participants' accounts
and any unallocated portion of the Trust fund on a pro rata basis. All expenses
of the Trustee relating directly to the acquisition and disposition of
investments constituting part of the Trust, and all taxes of any kind whatsoever
that may be levied or assessed under existing or future laws upon or in respect
of the Trust or the income thereof, shall be a charge against and paid from the
appropriate Plan participants' account.

         Section 7.  DIRECTIONS AND INDEMNIFICATION.

                  (a) IDENTITY OF ADMINISTRATOR AND INVESTMENT COMMITTEE. The
Trustee shall be fully protected in relying on the fact that the Investment
Committee and the Administrator under the Plan are the individuals or persons
named as such or such other individuals or persons as the Sponsor may notify the
Trustee in writing.

                  (b) DIRECTIONS FROM ADMINISTRATOR. Whenever the Administrator
provides a direction to the Trustee, the Trustee shall not be liable for any
loss, or by reason of any breach, arising from the direction (i) if the
direction is contained in a writing (or is oral and immediately confirmed in a
writing) signed by any individual whose name and signature have been submitted
(and not withdrawn) in writing to the Trustee by the Sponsor in the form
attached hereto as


<PAGE>   16
                                      -13-


Schedule "D", and (ii) if the Trustee reasonably believes the signature of the
individual to be genuine, unless it is clear on the direction's face that the
actions to be taken under the direction would be prohibited by the fiduciary
duty rules of section 404(a) of ERISA or would be contrary to the terms of the
Plan or this Agreement.

                  (c) DIRECTIONS FROM INVESTMENT COMMITTEE. Whenever the
Investment Committee provides a direction to the Trustee, the Trustee shall not
be liable for any loss, or by reason of any breach, arising from the direction
(i) if the direction is contained in a writing (or is oral and immediately
confirmed in a writing) signed by any individual whose name and signature have
been submitted (and not withdrawn) in writing to the Trustee by the Sponsor in
the form attached hereto as Schedule "E" and (ii) if the Trustee reasonably
believes the signature of the individual to be genuine, unless it is clear on
the direction's face that the actions to be taken under the direction would be
prohibited by the fiduciary duty rules of section 404(a) of ERISA or would be
contrary to the terms of the Plan or this Agreement.

                  (d) CO-FIDUCIARY LIABILITY. In any other case, the Trustee
shall not be liable for any loss, or by reason of any breach, arising from any
act or omission of another fiduciary under the Plan except as provided in
section 405(a) of ERISA.

                  (e) INDEMNIFICATION. The Sponsor shall indemnify the Trustee
against, and hold the Trustee harmless from, any and all loss, damage, penalty,
liability, cost, and expense, including without limitation, reasonable
attorneys' fees and disbursements, that may be incurred by, imposed upon, or
asserted against the Trustee by reason of any claim, regulatory proceeding, or
litigation arising from any act done or omitted to be done by any individual or
person with respect to the Plan or Trust, excepting only any and all loss, etc.,
arising from the Trustee's negligence or bad faith.



<PAGE>   17
                                      -14-


                  (f) SURVIVAL. The provisions of this Section 7 shall survive
the termination of this Agreement.

         Section 8.  RESIGNATION OR REMOVAL OF TRUSTEE.

                  (a) RESIGNATION. The Trustee may resign at any time upon sixty
(60) days' notice in writing to the Sponsor, unless a shorter period of notice
is agreed upon by the Sponsor.

                  (b) REMOVAL. The Sponsor may remove the Trustee at any time
upon sixty (60) days' notice in writing to the Trustee, unless a shorter period
of notice is agreed upon by the Trustee.

         Section 9.  SUCCESSOR TRUSTEE.

                  (a) APPOINTMENT. If the office of Trustee becomes vacant for
any reason, the Sponsor may in writing appoint a successor trustee under this
Agreement. The successor trustee shall have all of the rights, powers,
privileges, obligations, duties, liabilities, and immunities granted to the
Trustee under this Agreement. The successor trustee and predecessor trustee
shall not be liable for the acts or omissions of the other with respect to the
Trust.

                  (b) ACCEPTANCE. When the successor trustee accepts its
appointment under this Agreement, title to and possession of the Trust assets
shall immediately vest in the successor trustee without any further action on
the part of the predecessor trustee. The predecessor trustee shall execute all
instruments and do all acts that reasonably may be necessary or reasonably may
be requested in writing by the Sponsor or the successor trustee to vest title to
all Trust assets in the successor trustee or to deliver all Trust assets to the
successor trustee.

                  (c) CORPORATE ACTION. Any successor of the Trustee or
successor trustee, through sale or transfer of the business or trust department
of the Trustee or successor trustee, or



<PAGE>   18
                                      -15-


through reorganization, consolidation, or merger, or any similar transaction,
shall, upon consummation of the transaction, become the successor trustee under
this Agreement.

         Section 10. TERMINATION. This Agreement may be terminated, without
penalty to the Sponsor, at any time by the Sponsor upon sixty (60) days' notice
in writing to the Trustee. On the date of the termination of this Agreement, the
Trustee shall forthwith transfer and deliver to such individual or entity as the
Sponsor shall designate, all cash and assets then constituting the Trust. If, by
the termination date, the Sponsor has not notified the Trustee in writing as to
whom the assets and cash are to be transferred and delivered, the Trustee may
bring an appropriate action or proceeding for leave to deposit the assets and
cash in a court of competent jurisdiction. The Trustee shall be reimbursed by
the Sponsor for all costs and expenses of the action or proceeding including,
without limitation, reasonable attorneys' fees and disbursements.

         Section 11. RESIGNATION, REMOVAL, AND TERMINATION NOTICES. All notices
of resignation, removal, or termination under this Agreement must be in writing
and mailed to the party to which the notice is being given by certified or
registered mail, return receipt requested, to the Sponsor c/o Betty Green, HADCO
Corporation, 12A Manor Parkway, Salem, New Hampshire 03079 and James Hamilton,
General Counsel, Berlin, Hamilton & Dahmen, 73 Tremont Street, Boston,
Massachusetts 02108, and to the Trustee c/o John M. Kimpel, Fidelity
Investments, 82 Devonshire Street, Boston, Massachusetts 02109, or to such other
addresses as the parties have notified each other of in the foregoing manner.

         Section 12. DURATION. This Trust shall continue in effect without limit
as to time, subject, however, to the provisions of this Agreement relating to
amendment, modification, and termination thereof.


<PAGE>   19
                                      -16-


         Section 13. AMENDMENT OR MODIFICATION. This Agreement may be amended or
modified at any time and from time to time only by an instrument executed by
both the Sponsor and the Trustee. Notwithstanding the foregoing and not prior to
June 1, 1998, to reflect increased operating costs the Trustee may once each
calendar year amend Schedule "B" without the Sponsor's consent upon ninety (90)
days written notice to the Sponsor.

         Section 14.  GENERAL.

                  (a) PERFORMANCE BY TRUSTEE, ITS AGENTS OR AFFILIATES. The
Sponsor Acknowledges and authorizes that the services to be provided under this
Agreement shall be provided by the Trustee, its agents or affiliates, including
Fidelity Investments Institutional Operations Company or its successor, and that
certain of such services may be provided pursuant to one or more other
contractual agreements or relationships.

                  (b) ENTIRE AGREEMENT. This Agreement, including the Exhibits
attached hereto, contains all of the terms agreed upon between the parties with
respect to the subject matter hereof.

                  (c) WAIVER. No waiver by either party of any failure or
refusal to comply with an obligation hereunder shall be deemed a waiver of any
other or subsequent failure or refusal to so comply.

                  (d) SUCCESSORS AND ASSIGNS. The stipulations in this Agreement
shall inure to the benefit of, and shall bind, the successors and assigns of the
respective parties.

                  (e) PARTIAL INVALIDITY. If any term or provision of this
Agreement or the application thereof to any person or circumstances shall, to
any extent, be invalid or unenforceable, the remainder of this Agreement, or the
application of such term or provision to persons or circumstances other than
those as to which it is held invalid or unenforceable, shall


<PAGE>   20
                                      -17-


not be affected thereby, and each term and provision of this Agreement shall be
valid and enforceable to the fullest extent permitted by law.

                  (f) SECTION HEADINGS. The headings of the various sections and
subsections of this Agreement have been inserted only for the purposes of
convenience and are not part of this Agreement and shall not be deemed in any
manner to modify, explain, expand or restrict any of the provisions of this
Agreement.

         Section 15.  GOVERNING LAW.

                  (a) MASSACHUSETTS LAW CONTROLS. This Agreement is being made
in the Commonwealth of Massachusetts, and the Trust shall be administered as a
Massachusetts trust. The validity, construction, effect, and administration of
this Agreement shall be governed by and interpreted in accordance with the laws
of the Commonwealth of Massachusetts, except to the extent those laws are
superseded under section 514 of ERISA

                  (b) TRUST AGREEMENT CONTROLS.  The Trustee is not a party to
the Plan, and in the event of any conflict between the provisions of the Plan
and the provisions of this Agreement, the provisions of this Agreement shall
control.

                  [Remainder of page intentionally left blank]



<PAGE>   21
                                      -18-





         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their duly authorized officers as of the day and year first above
written.
                                           HADCO CORPORATION


Attest: /s/ James Hamilton                 By: /s/ Richard Saporito   5/24/96
        ----------------------------           ------------------------------
         Clerk                                   Vice President          Date


                                           FIDELITY MANAGEMENT TRUST COMPANY


Attest:  /s/ Douglas O. Kant               By: /s/ John O'Reiley     10/26/96
         ----------------------------          ------------------------------
         Assistant Clerk                         Vice President          Date