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                                                                   Exhibit 10.16

                          GSL INDUSTRIAL PARTNERS, L.P.
                           5858 WESTHEIMER, SUITE 800
                              HOUSTON, TEXAS 77057

                                 March 17, 2006

Suntron GCO, LP
2401 West Grandview Road
Phoenix, Arizona 85023
Attn: Hargopal (Paul) Singh

     Re:  Earnest Money Contract dated effective as of December 27, 2005 (the
          "Initial Contract"), by and between GSL INDUSTRIAL PARTNERS, L.P., as
          buyer ("Buyer"), and SUNTRON GCO, LP, as seller ("Seller"), regarding
          the sale and purchase of approximately 36 acres of developed land,
          plus an additional approximately 7.5 acres of undeveloped land,
          located at 1111 Gillingham Lane, Sugar Land, Fort Bend County, Texas
          (the "Property")

Dear Mr. Singh:

     Reference is hereby made to the Initial Contract, as amended by that
certain letter agreement dated February 2, 2006, executed by Seller and Buyer
(the "First Letter Agreement"), and as amended by that certain letter agreement
dated March 8, 2006, executed by Seller and Buyer (the "Second Letter
Agreement"). All capitalized terms used herein and not otherwise defined shall
have the same meanings as set forth in the Initial Contract as modified by the
First Letter Agreement and the Second Letter Agreement. On and after the date
hereof, all references to the "Contract" shall mean the Initial Contract as
modified by the First Letter Agreement and the Second Letter Agreement.

     For purposes of clarification at to the status of the transactions made the
subject of the Contract, Seller and Buyer acknowledge and agree that expiration
of the Inspection Period shall not occur, and Buyer's right to terminate the
Contract by the delivery of the Inspection Notice shall not expire, until March
21, 2006. In this regard, Seller and Buyer acknowledge that (a) the Property has
been platted in accordance with the terms of the Contract, (b) the issuance by
Carlisle SynTec Systems, Division of Carlisle Corporation of the confirmation of
the transferability of the roof warranties is imminent, (c) subject to Buyer's
reinspection of the roof on March 17, 2006, and the receipt, review and approval
of such reinspection report by Buyer on March 20, 2006, Buyer shall have fully
satisfied itself as to the physical condition of the Property, (d) Seller and
Buyer shall execute and deliver in escrow with the Title Company all documents
and instruments required to effect the Closing by March 22, 2006, and (e) Buyer
shall deliver the Initial Payment to the Title Company, and the Closing shall
occur, at such time as US Bank has delivered a written notice to the Title
Company stating that US Bank is prepared to close and fund the proceeds of
Suntron's Refinancing subject only to the receipt of the funds payable to Seller
at the Closing. For the avoidance of doubt, in accordance with the terms of the

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Suntron GCO, LP
Page 2 of 2


Second Letter Agreement, the Closing of the Contract shall occur simultaneous
with or after the actual closing and funding of Suntron's Refinancing.

     If this letter accurately reflects the Seller's understanding of the status
of the transactions made the subject of the Contract, please sign a copy of this
letter in the space provided below. Telecopy delivery of this letter signed by
each party to the other shall be binding and effective the same as if an
original signed copy has been delivered by each party to the other. This letter
may be executed in multiple counterparts, each of which shall be considered an
original, and all of which together shall constitute one and the same document.

     If you have any questions or comments with respect to any of the foregoing,
please do not hesitate to contact me.

                                        Sincerely yours,

                                        BUYER:

                                        GSL INDUSTRIAL PARTNERS, L.P.,
                                        a Texas limited partnership

                                        By: GSL Partners GP, LLC, a Texas
                                            limited liability company,
                                            its general partner


                                        By: /s/ WELCOME W. WILSON, SR.
                                            ------------------------------------
                                            Welcome W. Wilson, Sr.,
                                            Chairman and Chief
                                            Executive Officer


AGREED TO AND ACCEPTED
this         day of March, 2006:
     -------

SELLER:

SUNTRON GCO, LP,
a Texas limited partnership

By: Rodnic LLC, a Texas limited
    liability company, its general
    partner


By: /s/ JAMES A. DORAN
    ---------------------------------
    James A. Doran,
    Chief Financial Officer