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                                 Exhibit 10.3


                               BANKBOSTON, N.A.
                          BANCBOSTON SECURITIES INC.
                              100 FEDERAL STREET
                          BOSTON, MASSACHUSETTS 02110


                                 April 9, 1998


WesTower Corporation
17886 55th Avenue
Surrey, British Columbia V3S 6C8
Canada
Attention: Peter Lucas, Senior Vice President
             and Chief Financial Officer


    Re: Credit Facilities Commitment Letter
        -----------------------------------

Ladies and Gentlemen:

    You have informed us that Westower Corporation (the "Company") and its 
subsidiaries would like to have senior bank credit facilities of up to 
$75,000,000 (the "Credit Facilities") available in order to finance the 
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acquisition of telecommunications towers and businesses relating to building 
infrastructure and servicing such towers, working capital and other general 
business purposes. The Company has requested that (a) BankBoston, N.A. (the
"Bank") act as the exclusive administrative agent for the Credit Facilities and
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commit to provide the entire $75,000,000 principal amount of the Credit
Facilities and (b) BancBoston Securities Inc. ("BSI") agree to structure and
                                                ---
syndicate the Credit Facilities as exclusive adviser and arranger.

    1. Commitment. In connection with the foregoing, the Bank is pleased to 
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advise you of the Bank's commitment to provide the entire $75,000,000 principal 
amount of the Credit Facilities, upon the terms and subject to the conditions 
set forth or referred to in this commitment letter (the "Commitment Letter"), 
                                                         -----------------
including the Summary of Proposed Terms and Conditions attached hereto as 
Exhibit A (the "Term Sheet"). Those matters which are not covered by or made 
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clear in the Commitment Letter are subject to future mutual agreement of the 
parties.

    2. Syndication. The Bank will act as the exclusive administrative agent for 
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the Credit Facilities and BSI will act as the exclusive arranger, adviser and 
syndication manager for the Credit Facilities and, in such capacities, each of 
the Bank and BSI will perform the duties and exercise the authority customarily 
associated with such roles. No additional agents, co-agents,

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WesTower Corporation                     -2-                     April 9, 1998

arrangers or syndication managers will be appointed, unless the Company and each
of the Bank and BSI so agree. Prior to or after the execution of definitive 
documentation for the Credit Facilities, the Bank reserves the right to 
syndicate all or a portion of its commitment hereunder to one or more financial 
institutions upon consultation with the Company and BSI. Upon the acceptance by 
the Bank of the written commitment of any lender to provide a portion of the 
Credit Facilities, the Bank shall be released from a portion of its commitment 
hereunder in an aggregate amount equal to the commitment of such lender.

     BSI will manage all aspects of the syndication, including the selection of 
lenders, the determination of when BSI will approach potential lenders, titles 
for the lenders and the final allocations of the commitments among the lenders. 
The Company agrees to assist BSI actively in achieving a timely syndication that
is reasonably satisfactory to BSI, such assistance to include, among other 
things, (a) direct contact during the syndication between the Company's senior 
officers, representatives and advisors, on the one hand, and prospective 
lenders, on the other hand, at such times and places as BSI may reasonably 
request, (b) providing to BSI all financial and other information with respect 
to the Company and the transactions contemplated by this Commitment Letter that 
BSI may reasonably request, including but not limited to financial projections 
(the "Projections") relating to the foregoing, and (c) assistance in the 
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preparation of a confidential information memorandum and other marketing 
materials to be used in connection with the syndication.

     The Company agrees that, prior to and during the syndication of the Credit 
Facilities, the Company will not permit any offering, placement or arrangement 
of any competing issues of senior debt securities or senior commercial bank 
facilities of the Company and its subsidiaries.

     The Bank and BSI shall be entitled, with the consent of the Company (which
shall not be unreasonably withheld), to change the structure, terms or amount of
any portion of the Credit Facilities if the Bank and BSI determine that such
changes are advisable in order to ensure a successful syndication or an optimal
credit structure for the Credit Facilities so long as the aggregate amount of
the Credit Facilities shall not be reduced.

     3.  Conditions.  The commitment of the Bank and the agreement of BSI 
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hereunder are conditions upon (a) all information (other than the Projections) 
concerning the Company and the transactions contemplated by this Commitment 
Letter that has been or will be made available to the Bank or BSI by the Company
or any of its representatives in connection with the transactions contemplated 
by this Commitment Letter, when taken as a whole, is or will be at the closing 
complete and correct in all material respects and does not or will not at the 
closing contain any untrue statement of a material fact or omit to state a 
material fact necessary in order to make the statements contained therein not 
materially misleading in light of the
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WesTower Corporation                  -3-                       April 9, 1998

circumstances under which such statements are made and (b) the Projections 
that have been or will be made available to the Bank and BSI by the Company or 
any of its representatives in connection with the transactions contemplated by 
this Commitment Letter have been and will be prepared in good faith based upon 
reasonable assumptions. The Company agrees to supplement the information and 
projections referred to in clauses (a) and (b) above from time to time until 
completion of the syndication so that the statements in the preceding clauses 
remain correct. The statements set forth in this paragraph shall be superseded 
by the definitive documentation with respect to the Credit Facilities upon the 
execution and delivery thereof.

     The commitment of the Bank and the agreements of BSI hereunder are also 
conditioned upon the factors set forth in the Term Sheet, as well as the absence
of (i) any material adverse change in the business, assets, financial condition,
income or prospects of the Company and its subsidiaries since the date of the 
last audited financial statements previously furnished to the Bank, (ii) any 
material adverse change in the ability of the Company and its subsidiaries to 
operate in accordance with the financial projections furnished to the Bank or 
to comply with the proposed financial covenants, (iii) any material 
misstatements in or omissions from the materials that have previously been 
furnished by the Company to the Bank or BSI, (iv) satisfactory completion of the
due diligence investigation of the Company and its subsidiaries by the Bank and 
BSI and (v) any material adverse change in governmental regulation or policy 
affecting the Bank, BSI, the other lenders, the Company, its subsidiaries or the
proposed Credit Facilities or any material adverse disruption or material 
adverse change in financial, banking or capital markets since the date hereof 
which, in each case described in this clause (v), in the reasonable judgment of 
the Bank or BSI, makes it impracticable or inadvisable to proceed with the 
transactions contemplated hereby or the proposed syndication of the Credit 
Facilities.

     The commitment of the Bank and the agreements of BSI hereunder are also 
subject to the review of the final terms and documentation for the proposed 
$15,000,000 senior subordinated convertible note offering by the Company 
referred to in the Term Sheet, all of which must be satisfactory to the Bank and
BSI.

     In addition, the commitment of the Bank and the agreements of BSI hereunder
are subject to the negotiation, execution and delivery of definitive
documentation in customary form with respect to the Credit Facilities reasonably
satisfactory to the Bank and its counsel. Such documentation shall contain such
indemnities, covenants, representations and warranties, events of default,
conditions, definitions, and other terms and conditions as shall be customary
for transactions of this type and reasonably satisfactory to the Bank, the other
lenders, the Company and their respective counsel. If, in the course of
documenting the transaction and the Bank's continued analysis of financial and
other information relating to the development of financial and operating
covenants, the Bank discovers that any of the foregoing conditions will

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WesTower Corporation                                            April 9, 1998

in its reasonable judgment not be met, the Bank reserves the right to terminate 
any commitment, and BSI reserves the right to terminate any obligation, it may 
have hereunder with respect to the proposed Credit Facilities.

        4. Fees, Indemnification and Reimbursement. As consideration for the
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Bank's commitment hereunder and BSI's agreement to structure, arrange and 
syndicate the Credit Facilities and to provide advisory services in connection 
therewith, the Company agrees to pay to the Bank and BSI the respective fees as 
set forth in the Term Sheet and in the Fee Letter dated the date hereof and 
delivered herewith (the "Fee Letter"). The Company agrees that no lender will 
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receive any compensation of any kind for its participation in the Credit 
Facilities, except as expressly provided for in the Fee Letter.

        Whether or not the transactions contemplated hereby are consummated, the
Company agrees to indemnify and hold harmless the Bank, the other lenders under 
the Credit Facilities, BSI and their respective directors, officers, employees, 
affiliates, agents, attorneys, accountants, consultants and each other entity, 
if any, who controls the Bank, such other lenders or BSI and to hold such 
persons and entities harmless from and against all losses, claims, damages, 
liabilities and expenses, joint or several, which any such person or entity may 
incur arising out of or in connection with this Commitment Letter, the Fee 
Letter, the Term Sheet, the Credit Facilities, the use of proceeds of the 
extensions of credit thereunder or any related transaction or any claim, 
litigation, investigation or proceeding relating to any of the foregoing, 
regardless of whether any of such indemnified parties is a party thereto, and to
reimburse each of such indemnified parties upon demand for any legal or other
expenses incurred in connection with any of the foregoing; provided, however,
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that the foregoing indemnity will not, as to any indemnified party, apply to
losses, claims, damages, liabilities or related expenses to the extent resulting
from the willful misconduct or gross negligence of the proposed indemnified
party. No indemnified party shall be liable for any indirect or consequential
damages in connection with its activities related to the Credit Facilities.

        In addition, whether or not the transactions contemplated hereby are
consummated, the Company agrees to reimburse the Bank and BSI from time to time
on demand for reasonable out-of-pocket expenses (including, but not limited to,
reasonable expenses of our due diligence investigation, reasonable syndication
expenses, reasonable travel expenses and reasonable fees, disbursements and
charges of counsel), in each case incurred in connection with the Credit
Facilities and the preparation of this Commitment Letter, the Fee Letter, the
Term Sheet and the definitive documentation for the Credit Facilities.

        5. Confidentiality. The terms set forth in this Commitment Letter are 
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confidential and, without the prior consent of each party hereto, may not be 
disclosed to any person, except for disclosure in confidence to the company's 
accountants, attorneys and other advisors and to
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WesTower Corporation                 -5-                         April 9, 1998


each of the Bank's and BSI's attorneys and other advisors for purposes related 
to the transactions contemplated hereby, or where disclosure is required by law 
or by any subpoena or similar legal process, or in connection with the 
syndication of the Credit Facilities. Any information given by the Company or 
the Company's agents to the representatives of the Bank or BSI may be made 
available to any director, officer, partner, employee or other agent of the 
Bank, BSI or their affiliates, and may be disclosed where disclosure is required
by law or by any subpoena or similar legal process, or in connection with the 
syndication of the Credit Facilities.

        6. Termination. This Commitment Letter and the Fee Letter set forth the 
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proposal of the Bank and BSI with respect to the Credit Facilities and shall be 
considered withdrawn if the Bank and BSI have not received the enclosed copy of 
this Commitment Letter and Fee Letter signed by you by 5:00 p.m. on the second 
business day after the date of this letter.  If for any reason the Company, the 
proposed group of lenders and the Bank have not been able to agree to definitive
terms and conditions and enter into a definitive agreement with respect to the 
Credit Facilities prior to June 30, 1998, this proposal shall be considered 
terminated; provided, however, that the compensation, indemnification and 
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reimbursement provisions contained herein and in the Fee Letter shall remain in 
full force and effect notwithstanding the termination of this Commitment Letter 
or our commitment hereunder.

        7. General.  This Commitment Letter may not be amended, and no provision
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hereof shall be waived or modified, except by an instrument in writing signed by
the Bank, BSI and the Company. This Commitment Letter and the Fee Letter are the
only agreements between the Company, on one hand, and BSI and the Bank, on the
other hand, with respect to the Credit Facilities and set forth the entire
understanding of the parties with respect thereto. This Commitment Letter and
the commitment of the Bank and the agreements of BSI hereunder shall not be
assignable by the Company without the prior written consent of the Bank and BSI.
This Commitment Letter is solely for the benefit of the parties hereto and shall
not confer any benefits upon, or create any rights in favor of, any person other
than the parties hereto. The headings in this Commitment Letter are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof. This Commitment Letter may be executed in any number of
counterparts, which together shall constitute one agreement, and delivery of an
executed signature page by facsimile transmission shall be effective as delivery
of a manually executed counterpart. This Commitment Letter shall be governed by
and construed in accordance with the laws (other than the conflict of laws
rules) of The Commonwealth of Massachusetts.

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WesTower Corporation                 -6-                          April 9, 1998


        If the foregoing is in accordance with your understanding of our 
agreement, please sign this letter in the space indicated below and return it to
the Bank and BSI. The Bank and BSI are pleased to have the opportunity to assist
you in connection with this proposed financing transaction.

 
                               Very truly yours,

                                BANKBOSTON, N.A.


                                By /s/ Lenny Mason
                                   ------------------------------
                                   Title: Vice President


                                BANKBOSTON SECURITIES INC.

                                By /s/ Julia S. Van Trees
                                   ------------------------------
                                   Title: Managing Director


The foregoing is agreed to:

WESTOWER CORPORATION

By /s/ Peter Lucas
   -----------------------------
   Title: Sr. Vice President and
          Chief Financial Officer

Dated: April 10, 1998