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                                                                   EXHIBIT 10(b)

[COMERICA BANK LOGO] GUARANTY

As of October 30, 2003, the undersigned, for value received, unconditionally and
absolutely guarantee(s) to Comerica Bank ("Bank"), payment when due, whether by
stated maturity, demand, acceleration or otherwise, of all existing and future
indebtedness ("Indebtedness") to the Bank of PEERLESS MFG. CO. ("Borrower").
Indebtedness includes without limit any and all obligations or liabilities of
the Borrower to the Bank, whether absolute or contingent, direct or indirect,
voluntary or involuntary, liquidated or unliquidated, joint or several, known or
unknown; originally payable to the Bank or to a third party and subsequently
acquired by the Bank including, without limitation, late charges, loan fees or
charges and overdraft indebtedness; any and all indebtedness, obligations or
liabilities for which Borrower would otherwise be liable to the Bank were it not
for the invalidity, irregularity or unenforceability of them by reason of any
bankruptcy, insolvency or other law or order of any kind, or for any other
reason; any and all amendments, modifications, renewals and/or extensions of any
of the above; and all costs of collecting Indebtedness, including, without
limit, attorneys' fees. Any reference in this Guaranty to attorneys' fees shall
be deemed a reference to reasonable fees, charges, costs and expenses of counsel
and paralegals, whether inside or outside counsel is used, and whether or not a
suit or action is instituted, and to court costs if a suit or action is
instituted, and whether attorneys' fees or court costs are incurred at the trial
court level, on appeal, in a bankruptcy, administrative or probate proceeding or
otherwise. All costs shall be payable immediately by the undersigned when
incurred by the Bank, upon demand in writing, accompanied by reasonable detail
and explanation, and until paid shall bear interest at the highest per annum
rate applicable to any of the Indebtedness, but not in excess of the maximum
rate permitted by law.

1.       LIMITATION: The total obligation of the undersigned under this Guaranty
         is UNLIMITED unless specifically limited in the Additional Provisions
         of this Guaranty, and this obligation (whether unlimited or limited to
         the extent specified in the Additional Provisions) shall include, IN
         ADDITION TO any limited amount of principal guaranteed, all interest on
         that limited amount, and all costs incurred by the Bank in collection
         efforts against the Borrower and/or the undersigned or otherwise
         incurred by the Bank in any way relating to the Indebtedness, or this
         Guaranty, including without limit attorneys' fees. The undersigned
         agree(s) that (a) this limitation shall not be a limitation on the
         amount of Borrower's Indebtedness to the Bank; (b) any payments by the
         undersigned shall not reduce the maximum liability of the undersigned
         under this Guaranty unless written notice to that effect is actually
         received by the Bank at, or prior to, the time of the payment; and (c)
         the liability of the undersigned to the Bank shall at all times be
         deemed to be the aggregate liability of the undersigned under this
         Guaranty.

2.       NATURE OF GUARANTY: This is a continuing Guaranty of payment and not of
         collection and remains effective whether the Indebtedness is from time
         to time reduced and later increased or entirely extinguished and later
         reincurred. The undersigned deliver(s) this Guaranty based solely on
         the undersigned's independent investigation of (or decision not to
         investigate) the financial condition of Borrower and is (are) not
         relying on any information furnished by the Bank. The undersigned
         assume(s) full responsibility for obtaining any further information
         concerning the Borrower's financial condition, the status of the
         Indebtedness or any other matter which the undersigned may deem
         necessary or appropriate now or later. The undersigned knowingly
         accept(s) the full range of risk encompassed in this Guaranty, which
         risk includes, without limit, the possibility that Borrower may incur
         Indebtedness to the Bank after the financial condition of the Borrower,
         or the Borrower's ability to pay debts as they mature, has
         deteriorated.

3.       APPLICATION OF PAYMENTS: The undersigned authorize(s) the Bank, either
         before or after termination of this Guaranty, without notice to or
         demand on the undersigned and without affecting the undersigned's
         liability under this Guaranty, from time to time to: (a) apply any
         security and direct the order or manner of sale; and (b) apply payments
         received by the Bank from the Borrower to any indebtedness of the
         Borrower to the Bank, in such order as the Bank shall determine in its
         sole discretion, whether or not this indebtedness is covered by this
         Guaranty, and the undersigned waive(s) any provision of law regarding
         application of payments which specifies otherwise. The undersigned
         agree(s) to provide to the Bank copies of the undersigned's financial
         statements upon request.

4.       SECURITY: The undersigned pledge(s), assign(s) and grant(s) to the Bank
         a security interest in and lien upon and the right of setoff as to any
         and all property of the undersigned now or later in the possession of
         the Bank. The undersigned further assign(s) to the Bank as collateral
         for the obligations of the undersigned under this Guaranty all claims
         of any nature that the undersigned now or later has (have) against the
         Borrower (other than any claim under a deed of trust or mortgage
         covering California real property) with full right on the part of the
         Bank, in its own name or in the name of the undersigned, to collect and
         enforce these claims. The undersigned agree(s) that no security now or
         later held by the Bank for the payment of any Indebtedness, whether
         from the Borrower, any guarantor, or otherwise, and whether in the
         nature of a security interest, pledge, lien, assignment, setoff,
         suretyship, guaranty, indemnity, insurance or otherwise, shall affect
         in any manner the unconditional obligation of the undersigned under
         this Guaranty, and the Bank, in its sole discretion, without notice to
         the undersigned, may release, exchange, enforce and otherwise deal with
         any security without affecting in any manner the unconditional
         obligation of the undersigned under this Guaranty. The undersigned
         acknowledge(s) and agree(s) that the Bank has no obligation to acquire
         or perfect any lien on or security interest in any asset(s), whether
         realty or personalty, to secure payment of the Indebtedness, and the
         undersigned is (are) not relying upon any asset(s) in which the Bank
         has or may have a lien or security interest for payment of the
         Indebtedness.

5.       [INTENTIONALLY OMITTED].

6.       TERMINATION: Any of the undersigned may terminate their obligation
         under this Guaranty as to future Indebtedness (except as provided
         below) by (and only by) delivering written notice of termination to an
         officer of the Bank and receiving from an officer of the Bank written
         acknowledgement of delivery; provided, however, the termination shall
         not be effective until the opening of business on the fifth (5th) day
         ("effective date") following written acknowledgement of delivery. Any
         termination shall not affect in any way the unconditional obligations
         of the remaining guarantor(s), whether or not the termination is known
         to the remaining guarantor(s). Any termination shall not affect in any
         way the unconditional obligations of the terminating guarantor(s) as to
         any Indebtedness existing at the effective date of termination or any
         Indebtedness created after that pursuant to any commitment or agreement
         of the Bank or pursuant to any Borrower loan with the Bank existing at
         the effective date of termination (whether advances or readvances by
         the Bank after the effective date of termination are optional or
         obligatory), or any modifications, extensions or renewals of any of
         this Indebtedness, whether in whole or in part, and as to all of this
         Indebtedness and modifications, extensions or renewals of it, this
         Guaranty shall continue effective until the same shall have been fully
         paid. The Bank has no duty to give notice of termination by any
         guarantor(s) to any remaining guarantor(s). The undersigned shall
         indemnify the Bank against all claims, damages, costs and expenses
         (collectively, the "Indemnified Matters"), INCLUDING ANY CLAIMS,
         DAMAGES, COSTS AND

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         EXPENSES RESULTING FROM BANK'S OWN NEGLIGENCE, except and to the extent
         (but only to the extent) caused by Bank's gross negligence or wilful
         misconduct, including, without limit, attorneys' fees, incurred by the
         Bank in connection with any suit, claim or action against the Bank
         arising out of any modification or termination of a Borrower loan or
         any refusal by the Bank to extend additional credit in connection with
         the termination of this Guaranty. Upon Bank's receipt of written notice
         of any such Indemnified Matter, Bank will provide to Debtor notice, in
         writing accompanied by reasonable detail, of such Indemnified Matter,
         but any failure by Bank to provide such notice to Debtor shall not
         impair or otherwise affect the rights of Bank to be indemnified and
         held harmless under this Section.

7.       REINSTATEMENT: Notwithstanding any prior revocation, termination,
         surrender or discharge of this Guaranty (or of any lien, pledge or
         security interest securing this Guaranty) in whole or in part, the
         effectiveness of this Guaranty, and of all liens, pledges and security
         interests securing this Guaranty, shall automatically continue or be
         reinstated in the event that any payment received or credit given by
         the Bank in respect of the Indebtedness is returned, disgorged or
         rescinded under any applicable state or federal law, including, without
         limitation, laws pertaining to bankruptcy or insolvency, in which case
         this Guaranty, and all liens, pledges and security interests securing
         this Guaranty, shall be enforceable against the undersigned as if the
         returned, disgorged or rescinded payment or credit had not been
         received or given by the Bank, and whether or not the Bank relied upon
         this payment or credit or changed its position as a consequence of it.
         In the event of continuation or reinstatement of this Guaranty and the
         liens, pledges and security interests securing it, the undersigned
         agree(s) upon demand by the Bank to execute and deliver to the Bank
         those documents which the Bank determines are appropriate to further
         evidence (in the public records or otherwise) this continuation or
         reinstatement, although the failure of the undersigned to do so shall
         not affect in any way the reinstatement or continuation. If the
         undersigned do(es) not execute and deliver to the Bank upon demand such
         documents, the Bank and each Bank officer is irrevocably appointed
         (which appointment is coupled with an interest) the true and lawful
         attorney of the undersigned (with full power of substitution) to
         execute and deliver such documents in the name and on behalf of the
         undersigned.

8.       WAIVERS: The undersigned, to the extent not expressly prohibited by
         applicable law, waive(s) any right to require the Bank to: (a) proceed
         against any person or property; (b) give notice of the terms, time and
         place of any public or private sale of personal property security held
         from the Borrower or any other person, or otherwise comply with the
         provisions of Sections 9-611 or 9-621 of the Texas or other applicable
         Uniform Commercial Code, as the same may be amended, revised or
         replaced from time to time; or (c) pursue any other remedy in the
         Bank's power. The undersigned waive(s) notice of acceptance of this
         Guaranty and presentment, demand, protest, notice of protest, dishonor,
         notice of dishonor, notice of default, notice of intent to accelerate
         or demand payment or notice of acceleration of any Indebtedness, any
         and all other notices to which the undersigned might otherwise be
         entitled, and diligence in collecting any Indebtedness, and all rights
         of a guarantor under Rule 31, Texas Rules of Civil Procedure, Chapter
         34 of the Texas Business and Commerce Code, or Section 17.001 of the
         Texas Civil Practice and Remedies Code, and agree(s) that the Bank may,
         once or any number of times, modify the terms of any Indebtedness,
         compromise, extend, increase, accelerate, renew or forbear to enforce
         payment of any or all Indebtedness, or permit the Borrower to incur
         additional Indebtedness, all without notice to the undersigned and
         without affecting in any manner the unconditional obligation of the
         undersigned under this Guaranty.

         The undersigned unconditionally and irrevocably waive(s) each and every
         defense and setoff of any nature which, under principles of guaranty or
         otherwise, would operate to impair or diminish in any way the
         obligation of the undersigned under this Guaranty, and acknowledge(s)
         that each such waiver is by this reference incorporated into each
         security agreement, collateral assignment, pledge and/or other document
         from the undersigned now or later securing this Guaranty and/or the
         Indebtedness, and acknowledge(s) that as of the date of this Guaranty
         no such defense or setoff exists.

9.       WAIVER OF SUBROGATION: The undersigned waive(s) any and all rights
         (whether by subrogation, indemnity, reimbursement, or otherwise) to
         recover from the Borrower any amounts paid by the undersigned pursuant
         to this Guaranty until the Indebtedness has been paid in full.

10.      SALE/ASSIGNMENT: The undersigned acknowledge(s) that the Bank has the
         right to sell, assign, transfer, negotiate, or grant participations in
         all or any part of the Indebtedness and any related obligations,
         including, without limit, this Guaranty, as provided in that certain
         Credit Agreement of even date herewith between Borrower and the Bank,
         without notice to the undersigned and that the Bank may disclose any
         documents and information which the Bank now has or later acquires
         relating to the undersigned or to the Borrower or the Indebtedness in
         connection with such sale, assignment, transfer, negotiation, or grant.
         The undersigned agree(s) that the Bank may provide information relating
         to this Guaranty or relating to the undersigned to the Bank's parent,
         affiliates, subsidiaries and service providers.

11.      GENERAL: This Guaranty constitutes the entire agreement of the
         undersigned and the Bank with respect to the subject matter of this
         Guaranty. No waiver, consent, modification or change of the terms of
         the Guaranty shall bind any of the undersigned or the Bank unless in
         writing and signed by the waiving party or an authorized officer of the
         waiving party, and then this waiver, consent, modification or change
         shall be effective only in the specific instance and for the specific
         purpose given. This Guaranty shall inure to the benefit of the Bank and
         its successors and assigns and shall be binding on the undersigned and
         the undersigned's legal representatives, successors and assigns
         including, without limit, any debtor in possession or trustee in
         bankruptcy for any of the undersigned. The undersigned has (have)
         knowingly and voluntarily entered into this Guaranty in good faith for
         the purpose of inducing the Bank to extend credit or make other
         financial accommodations to the Borrower. If any provision of this
         Guaranty is unenforceable in whole or in part for any reason, the
         remaining provisions shall continue to be effective. THIS GUARANTY
         SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS
         OF THE STATE OF TEXAS, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES.

12.      HEADINGS: Headings in this Agreement are included for the convenience
         of reference only and shall not constitute a part of this Agreement for
         any purpose.

13.      ADDITIONAL PROVISIONS: None.

14.      JURY TRIAL WAIVER: THE UNDERSIGNED AND BANK, BY ACCEPTANCE OF THIS
         GUARANTY, ACKNOWLEDGE THAT THE RIGHT TO TRIAL BY JURY IS A
         CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED. EACH PARTY, AFTER
         CONSULTING (OR HAVING HAD THE OPPORTUNITY TO CONSULT) WITH COUNSEL OF
         THEIR CHOICE, KNOWINGLY AND VOLUNTARILY, AND FOR THEIR MUTUAL BENEFIT
         WAIVES ANY RIGHT TO TRIAL BY JURY IN THE EVENT OF LITIGATION REGARDING
         THE PERFORMANCE OR ENFORCEMENT OF, OR IN ANY WAY RELATED TO, THIS
         GUARANTY OR THE INDEBTEDNESS.

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15.      THIS WRITTEN LOAN AGREEMENT (AS DEFINED BY SECTION 26.02 OF THE TEXAS
         BUSINESS AND COMMERCE CODE) REPRESENTS THE FINAL AGREEMENT BETWEEN THE
         PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
         CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE
         NO UNWRITTEN OR ORAL AGREEMENTS BETWEEN THE PARTIES.

IN WITNESS WHEREOF, Guarantor(s) has (have) signed and delivered this Guaranty
the day and year first written above.

                                    GUARANTOR:

                                    PMC ACQUISITION, INC.

                                    By: /s/ Richard L. Travis, Jr.
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                                                     SIGNATURE OF

                                        Its: Chief Financial Officer
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                                         TITLE (IF APPLICABLE)

                                    GUARANTOR"S ADDRESS:

                                    2819 Wallnut Hill Lane
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                                    STREET ADDRESS

                                    Dallas              TX              75354
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                                    CITY              STATE            ZIP CODE