Exhibit 10.58
                         



               AMENDMENT NO. 1 AND WAIVER TO AMENDED AND RESTATED
                           LOAN AND SECURITY AGREEMENT


         This Amendment No. 1 and Waiver (this  "Amendment")  is entered into as
of December 30, 1996 by and among MK Rail  Corporation,  a Delaware  corporation
("MKR"),  with its chief executive office at 1200 Reedsdale Street,  Pittsburgh,
Pennsylvania  15233; Motor Coils  Manufacturing Co., a Pennsylvania  corporation
("Motor  Coils");  MK  Engine  Systems  Company,  Inc.,  a New York  Corporation
("MKES"); Clark Industries, Inc., an Illinois corporation ("Clark"); Power Parts
Company, a Nevada  corporation  ("Power Parts");  Touchstone,  Inc., a Tennessee
corporation  ("Touchstone");  Power  Parts  Sign Co.,  an  Illinois  corporation
("Sign")  (each  of  MKR  and  the  Component   Subsidiaries  a  "Borrower"  and
collectively the "Borrowers"), and BankAmerica Business Credit, Inc., a Delaware
corporation, individually as a lender ("Lender") and as agent ("Agent").

                                    RECITALS


         A. The  Borrowers,  the Agent and the Lender are party to that  certain
Amended and Restated Loan and Security  Agreement dated as of September 10, 1996
(as previously  amended,  the "Credit  Agreement").  Unless otherwise  specified
herein,  capitalized  terms  used in this  Amendment  shall  have  the  meanings
ascribed to them by the Credit Agreement.

         B. Immediately prior to the execution of this Amendment,  the Agent and
the Lender  entered into  Assignment and  Acceptance  Agreements  dated the date
hereof (the "Assignment Agreements") with each of Heller Financial,  Inc., Green
Tree  Financial  Servicing  Corporation  and Star Bank, N.A  (collectively,  the
"Former Lenders"),  pursuant to which the Lender purchased from such Persons all
of their  outstanding  Loans and  commitments  under the Credit  Agreement  (the
"Buyout"),  and paid them (on behalf of and with the consent of the Borrowers) a
prepayment  fee for  agreeing  to the  Buyout,  plus any and all unpaid  accrued
interest and fees owed by the Borrowers through the date hereof or the Effective
Date,  whichever  is later,  all  amounts as set forth in each  Exhibit A to the
Assignment Agreements.

         C.  The  Borrowers  intend  to  implement  a  corporate  restructuring,
effective as of January 1, 1997, as set forth in Exhibit A hereto.

         D. The  Borrowers,  the  Lender  and the Agent wish to amend the Credit
Agreement and waive certain provisions thereof with respect to (a) the corporate
restructuring,  (b) the maturity  date of the Loans and (c) the rate of interest
on the Loans, all pursuant to the terms as set forth below.


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         Now,  therefore,  in  consideration  of the mutual execution hereof and
other good and valuable consideration, the parties hereto agree as follows:

         1. Amendment to Credit Agreement. Upon the "Effective Date" (as defined
below), the Credit Agreement shall be amended as follows:

         (a) The  following  definitions  in  Section  1.1 are  amended in their
entirety to read as follows:

  o     "'Stated Termination Date' means September 30, 1997."

  o     "'Applicable Revolver Base Rate Margin' shall mean one half of one
        percent (0.50%)."

  o     "'Applicable Revolver LIBOR Margin' shall mean two percent (2%)."

  o     "'Applicable Term Base Rate Margin' shall mean three-quarters of
        one percent (0.75%)."

  o     "'Applicable Term LIBOR Margin' shall mean two and one-quarter
        percent (2.25%)."

  o     "'Default Rate' means a fluctuating per annum interest rate at all times
          ------------                      ---------
        equal to the sum of (a) the Interest Rate for each Loan or Obligation
        which would be derived by applying the otherwise Applicable
        Margin, plus (b) two percent (2.0%).  Each Default Rate shall be
                ----
        adjusted simultaneously with any change in the applicable Interest
        Rate.  In addition, with respect to Letters of Credit, the Default Rate
        shall mean an increase in the Letter of Credit Fee by two percent
        (2.0%) per annum."

         (b) The second sentence of Section 2.2(c) is amended in its entirety to
read as follows:

                           "The  Term  Loan  Notes  delivered  to the  Agent (on
                  behalf of the Lenders) shall be dated the Closing Date and the
                  principal  amount of the Term Loan  shall  mature in  thirteen
                  (13)  monthly  installments.  Each of the  first  twelve  (12)
                  installments  of principal shall be payable in an amount equal
                  to $133,334 (and paid ratably by the Borrowers  receiving Term
                  Loans) and shall be  payable  on the first day of each  month,
                  commencing on October 1, 1996 and ending on September 1, 1997,
                  and the final  installment of principal on the Term Loan shall
                  be payable in an amount equal to $6,399,992 or, if

                                       -2-


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different,  the then remaining  principal balance of the Term Loan, and shall be
payable on the Stated Termination Date."
     (c) Thefirst paragraph of Section 3.1(a)(iii) is amended in its entirety to
 read as follows: 
               "(iii)  Without  limiting  any other  restrictions  herein on the
               availability  of LIBOR Rate Loans,  the Borrowers  shall not have
               the option to elect,  designate,  continue  or convert  any Loans
               into LIBOR Rate Loans on the Closing  Date  (through  October 31,
               1996) or at any time when a Default  or an Event of  Default  has
               occurred and is continuing." (d) Section 3.1(b) is amended in its
               entirety to read as follows:

                                    "(b).   Intentionally Omitted."

                           (e)      Section 3.2(c) is amended in its entirety to
                                    read as follows:

                                    "(c) If upon the  expiration of any Interest
                                    Period  applicable to LIBOR Rate Loans,  MKR
                                    has failed to select  timely a new  Interest
                                    Period to be  applicable to LIBOR Rate Loans
                                    or if any  Default or Event of Default  then
                                    exists,  then the applicable  Borrower shall
                                    be deemed to have  elected to  convert  such
                                    LIBOR   Rate  Loans  into  Base  Rate  Loans
                                    effective as of the expiration  date of such
                                    Interest Period."

                           (f)      Section 4.2 is amended  in its  entirety  to
                                    read as follows:

                                    "4.2  Termination of Facility;  Prepayments.
                                    The Borrowers may terminate  this  Agreement
                                    upon at least ten (10) Business  Days' prior
                                    written notice from MKR to the Agent and the
                                    Lenders,  upon  (a) the  payment  in full in
                                    cash of all outstanding Loans, together with
                                    accrued    interest    thereon,    and   the
                                    cancellation of all  outstanding  Letters of
                                    Credit,  (b) the  payment in full in cash of
                                    all other Obligations  together with accrued
                                    interest  thereon,  and (c) with  respect to
                                    any LIBOR Rate Loans  prepaid in  connection
                                    with   such   termination   prior   to   the
                                    expiration   date  of  the  Interest  Period
                                    applicable  thereto,   the  payment  of  the
                                    amounts described in Section 5.4."

                           (g)      Schedules   8.5  and  8.7  are  deleted  and
                                    Schedules  8.5 and 8.7  attached  hereto are
                                    hereby   substituted   in   their   entirety
                                    therefor.


                                       -3-


<PAGE>



                           (h)      The  Lender's  signature  page to the Credit
                                    Agreement is amended and  substituted in its
                                    entirety  by  the  form  of  signature  page
                                    signed by the  Lender and  attached  to this
                                    Amendment.

                  2.       Consent and Waiver.

                           (a)  Notwithstanding  anything  to the  contrary  set
         forth in  Section  9.21 of the Credit  Agreement,  the Agent and Lender
         consent to MKR creating the following new wholly-owned  subsidiaries as
         of January 1, 1997:

             (i)     MotivePower Investments Ltd., a Delaware corporation;

             (ii)    MotivePower Investments, Inc., a Delaware corporation;

             (iii)   Boise Locomotive Company, a Delaware corporation; and

             (iv)    Motive Power Foreign Sales Corporation, a Barbados
                     corporation;

         provided,   however,   that  the  consent  in  this  paragraph  (a)  is
         conditioned on the Borrower's acknowledgment and agreement that each of
         these   subsidiaries   shall  not  (i)  conduct  business  or  business
         operations,  (ii) start  operations  without the written consent of the
         Agent and (iii)  have  assets or  liabilities  of any kind in excess of
         $10,000 in the aggregate.

                           (b)  Notwithstanding  anything  to the  contrary  set
forth in Section 9.9 of the Credit  Agreement,  the Agent and the Lender consent
to (a) the merger of MotivePower Industries, Inc. into MKR to be effective as of
January 1, 1997 and (b) the  dissolution of Sign and AMS  Manufacturing  Company
(f/k/a Alert Mfg. & Supply Co.) to be effective as of January 1, 1997.

                           (c)  Notwithstanding  anything  to the  contrary  set
forth in  Section  7.3(j) of the  Credit  Agreement,  the  Agent and the  Lender
consent to the Borrowers name changes as set forth in Exhibit A hereto.

                           (d) No later  than  January 6,  1997,  the  Borrowers
shall provide to the Agent and the Lender written evidence in form and substance
acceptable to the Agent and the Lender of the effectiveness of (i) the Merger of
MotivePower  Industries,  Inc.  into MKR, (ii) the  dissolution  of Sign and AMS
Manufacturing  Company  (f/k/a  Alert  Mfg.  & Supply  Co.),  and (iii) the name
changes as set forth in Exhibit A hereto.

                           3.  Representations  and  Warranties of the Borrower.
Each of the Borrowers represents and warrants that:


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<PAGE>



                           (a) The  execution,  delivery and  performance by the
         Borrowers of this Amendment have been duly  authorized by all necessary
         corporate action and that this Amendment is a legal,  valid and binding
         obligation  of the  Borrowers  enforceable  against  the  Borrowers  in
         accordance  with its terms,  except as the  enforcement  thereof may be
         subject to (i) the  effect of any  applicable  bankruptcy,  insolvency,
         reorganization,  moratorium or similar law affecting  creditors' rights
         generally and (ii) general  principles of equity (regardless of whether
         such enforcement is sought in a proceeding in equity or at law);

                           (b)  Each  of  the   representations  and  warranties
         contained  in the Credit  Agreement is true and correct in all material
         respects on and as of the date hereof as if made on the date hereof;

                           (c) The  execution,  delivery and  performance by the
         Borrowers of this  Amendment,  and the  performance by the Borrowers of
         the  Credit  Agreement  (as  amended  hereby)  do not and  will not (i)
         violate any provision of any law, rule or regulation  applicable to the
         Borrowers,  the Certificate or Articles of  Incorporation  or Bylaws of
         the  Borrowers  or any order,  judgment or decree of any court or other
         agency or  government  binding on any  Borrower,  (ii)  conflict  with,
         result in a breach of or  constitute  (with due notice or lapse of time
         or  both)  a  default  under  any  contract,   agreement,  mortgage  or
         obligation  of any  Borrower  except  where the  Borrowers  shall  have
         obtained  waivers or consents from the other parties to such agreements
         and  disclosed  the same to the Agent,  (iii)  result in or require the
         creation  or  imposition  of  any  lien  upon  any  of  the  Borrowers'
         properties or assets (other than Liens  permitted under Section 9.19 of
         the Credit  Agreement) or (iv) require any approval of  stockholders or
         any  approval or consent of any Person under any  contract,  agreement,
         mortgage or  obligation  to which any  Borrower is a party (or by which
         its  assets or  properties  are  bound)  except  for the  approvals  or
         consents  which  will be  obtained  on or before  the date  hereof  and
         disclosed in writing to the Agent.

                           (d) After giving effect to this Amendment, no Default
         or Event of Default has occurred and is continuing.

                           (e) The  Borrowers  authorize  and agree  that on the
         Effective  Date (i) MKR will be deemed to have  made a  Revolving  Loan
         borrowing  (and to have provided the funds to the Agent for the use set
         forth below) in an aggregate  amount equal to the prepayment fee as set
         forth on each Exhibit A to the Assignment  Agreements of  approximately
         $1,000,000 in the aggregate (the  "Prepayment  Fee"),  plus any and all
         unpaid  accrued  interest and fees owed by the  Borrowers to the Former
         Lenders  through the date hereof or the  Effective  Date,  whichever is
         later as set forth on each Exhibit A to the Assignment  Agreements (the
         "Payoff  Amount"),and  (ii) the  Agent  will use the  proceeds  of such
         Revolving  Loan  borrowing  on  behalf of the  Borrowers  to pay to the
         Former  Lenders  the   Prepayment   Fee,  plus  the  Payoff  Amount  as
         consideration for consenting to the Buyout.


                                       -5-


<PAGE>



               4.  Effective  Time.  Sections  1 and 2 of this  Amendment  shall
          become effective  - upon:

                           (a)  the  execution   and  delivery   hereof  by  the
         Borrowers, the Lender and the Agent;

                           (b)  the  payment  by the  Borrowers  to  BankAmerica
         Business Credit, Inc., individually, on the date hereof of a prepayment
         fee of  $500,000 in  immediately  available  funds,  which fee shall be
         deemed fully  earned and  non-refundable  on the date  hereof,  and MKR
         hereby  authorizes  such payment to be made as a revolving loan advance
         to MKR;

                           (c) the  delivery  of a legal  opinion  from  Doepken
         Keevican & Weiss, counsel to the Borrowers,  as to all the transactions
         described herein;

                           (d) receipt by the Agent of evidence of the corporate
         restructuring  and the other  documents and  deliveries as set forth in
         the  Closing  Memorandum  attached  hereto as Exhibit B all in form and
         substance acceptable to the Agent; and

                           (e)  the  execution  and  delivery  of  that  certain
         Commitment  Letter and Fee Letter among MKR, Bank of America  Illinois,
         Bank of America NT & SA and BA Securities, Inc.

In the event the Effective Time has not occurred on or before 5:00 p.m. (Chicago
time) December 31, 1996,  Sections 1 and 2 hereof shall not become operative and
shall be of no force or effect.

                  5.       Reference to and Effect Upon the Credit Agreement.

                           (a) Except as specifically  amended above, the Credit
         Agreement and the other Loan  Documents  shall remain in full force and
         effect and are hereby ratified and confirmed.

                           (b) The execution, delivery and effectiveness of this
         Amendment  shall not operate as a waiver of any right,  power or remedy
         of the Agent or any  Lender  under  the  Credit  Agreement  or any Loan
         Document,  nor  constitute  a waiver  of any  provision  of the  Credit
         Agreement  or any Loan  Document,  except  as  specifically  set  forth
         herein. Upon the effectiveness of this Amendment, each reference in the
         Credit Agreement to "this Agreement",  "hereunder",  "hereof", "herein"
         or words of similar  import shall mean and be a reference to the Credit
         Agreement as amended hereby.

                  6.       Costs and Expenses.

                           (a) The Borrower hereby affirms its obligation  under
         Section 15.7 of the Credit  Agreement  to  reimburse  the Agent and the
         Lender for all reasonable costs, internal

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<PAGE>



         charges  and  out-of-pocket  expenses  paid or incurred by the Agent in
         connection with the preparation, negotiation, execution and delivery of
         this  Amendment,  including but not limited to the attorneys'  fees and
         time charges of attorneys (and the allocated cost of in-house  counsel)
         for the Agent with respect thereto.

                  7.  GOVERNING  LAW.  THIS  AMENDMENT  SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE  WITH THE INTERNAL LAWS (AS OPPOSED TO CONFLICTS OF LAWS
PROVISIONS)  OF THE STATE OF ILLINOIS;  PROVIDED  THAT THE LENDERS AND THE AGENT
SHALL RETAIN ALL RIGHTS ARISING UNDER FEDERAL LAW.

                  8. Headings.  Section  headings in this Amendment are included
herein for convenience of reference only and shall not constitute a part of this
Amendment for any other purposes.

                  9. Counterparts.  This Amendment may be executed in any number
of counterparts,  each of which when so executed shall be deemed an original but
all such counterparts shall constitute one and the same instrument.

                  10.  JURY  TRIAL  WAIVER.  THE  BORROWERS,  THE  AGENT AND THE
LENDERS HEREBY WAIVE ANY RIGHT TO A TRIAL BY JURY IN ANY ACTION OR PROCEEDING TO
ENFORCE OR DEFEND AND RIGHTS UNDER THIS  AMENDMENT,  THE LOAN DOCUMENTS OR UNDER
ANY AMENDMENT,  INSTRUMENT,  DOCUMENT OR AGREEMENT DELIVERED OR WHICH MAY IN THE
FUTURE  BE  DELIVERED  IN  CONNECTION  HEREWITH  OR  ARISING  FROM  ANY  LENDING
RELATIONSHIP  EXISTING IN CONNECTION  WITH THIS  AMENDMENT OR ANY LOAN DOCUMENT,
AND AGREE THAT ANY SUCH ACTION OR  PROCEEDING  SHALL BE TRIED BEFORE A COURT AND
NOT BEFORE A JURY.

                  11.  Releases.  In further  consideration  of the execution of
this  Amendment by the Agent and the Lenders,  the Borrowers  hereby release the
Agent and the Lenders and all current and future  holders of  assignments  of or
participations  in the Obligations and their  respective  affiliates,  officers,
employees, directors, agents and attorneys (collectively,  the "Releasees") from
any and all claims, demands, liabilities, responsibilities,  disputes, causes of
action (whether at law or in equity) and obligations of every nature whatsoever,
whether  liquidated  or  unliquidated,  known or unknown,  matured or unmatured,
fixed or contingent (collectively, "Claims") that the Borrowers may have against
the Releasees  which arise from or relate to any actions which the Releasees may
have taken or omitted to take on or prior to the date hereof with respect to the
Obligations,  any Collateral,  the Credit Agreement, any other Loan Document and
any third parties liable in whole or in part for the  Obligations.  For purposes
of the release contained in this paragraph,  the term "Borrowers" shall mean and
include the  Borrowers  and their  successors  and assigns,  including,  without
limitation,   any   trustees   acting  on  behalf  of  such   parties   and  any
debtor-in-possession in respect of any such party.


                                       -7-


<PAGE>



                  12.  Reaffirmation  of  Guaranty.  Each of the  Borrowers as a
guarantor under Article 16 of the Credit  Agreement  hereby (i) acknowledges and
reaffirms  all of its  obligations  and  undertakings  under the guaranty  under
Article 16 of the  Credit  Agreement,  and (ii)  acknowledges  and  agrees  that
subsequent  to, and taking into  account  this  Amendment,  the  guaranty  under
Article 16 of the Credit  Agreement is and shall remain in full force and effect
in accordance with the terms thereof.

                  13.  Date Down on Title  Insurance.  If on March 31,  1997 the
Lender still has any  outstanding  Commitment  under the Credit  Agreement,  the
Borrowers shall deliver to the Agent and the Lender date down  endorsements  for
the  title  policies  with  respect  to the  Mortgages  in  form  and  substance
acceptable to the Agent.


                                       -8-


<PAGE>



                  IN WITNESS  WHEREOF,  the parties have executed this Amendment
as of the date and year first above written.

                                                    "BORROWERS"


Power Parts Company                MK Rail Corporation

By:                                         By:
Title:                             Title:

Touchstone, Inc.                   Motor Coils Manufacturing Co.

By:                                         By:
Title:                             Title:

Power Parts Sign Co.                        MK Engine Systems Company, Inc.

By:                                         By:
Title:                             Title:

                                   Clark Industries, Inc.

                                   By:
                                   Title:



Acknowledged and agreed to:

AMS Manufacturing Company
 (f/k/a Alert Mfg & Supply Co.)

By:
Title:

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<PAGE>




Commitment:        $75,000,000           BANKAMERICA BUSINESS CREDIT, INC.,
                                         individually as a Lender and as Agent
Revolving Loan
 Commitment:       $67,000,000
                                         By:
Term Loan
 Commitment:       $8,000,000            Its:

Pro Rate Share:    100%

                                      -10-


<PAGE>



                                    EXHIBIT A

                             Corporate Restructuring


Existing Name                          New Name as of January 1, 1997
-------------                          ------------------------------



                                      -11-


<PAGE>


                                                     EXHIBIT B

                                                Closing Memorandum




































<PAGE>

                                      -12-