SIXTH MODIFICATION AGREEMENT              EXHIBIT 10.3


DATE:             November 26, 1995

PARTIES:          Borrower:  MILBURN INVESTMENTS, INC.,
                             a Texas corporation.

                  Bank:      BANK ONE, ARIZONA, NA,
                             a national banking association.

RECITALS:

         A. Bank has  extended to  Borrower  credit  ("Loan")  in the  principal
amount of  $25,000,000.00  pursuant to the Amended and Restated Loan  Agreement,
dated  October 28, 1994 ("Loan  Agreement"),  and  evidenced by the  Replacement
Promissory  Note,  dated October 28, 1994 ("Note").  The unpaid principal of the
Loan as of the date hereof is $0.

         B. The Loan is secured by, among other things,  various Deeds of Trust,
Assignment of Leases and Rents,  Security  Agreement  and  Financing  Statements
("Deeds of  Trust"),  by  Borrower,  as  trustor,  for the  benefit of Bank,  as
beneficiary, recorded in records of Bell, Travis, and Williamson Counties, Texas
(the agreements,  documents,  and instruments securing the Loan and the Note are
referred to individually and collectively as the "Security Documents").

         C.  Bank and  Borrower  have  executed  and  delivered  previously  the
following  agreements  ("Modifications")  modifying  the terms of the Loan,  the
Note, the Loan  Agreement,  and/or the Security  Documents:  First  Modification
Agreement,  dated December 8, 1994, Second Modification  Agreement,  dated March
15, 1995, Third Modification Agreement,  dated May 19, 1995, Fourth Modification
Agreement,  dated  July  28,  1995,  and  Fifth  Modification  Agreement,  dated
September 26, 1995. (The Note, the Loan Agreement,  the Security Documents,  any
arbitration resolution, any environmental certification and indemnity agreement,
and all other agreements,  documents,  and instruments evidencing,  securing, or
otherwise relating to the Loan, as modified in the Modifications,  are sometimes
referred to individually and collectively as the "Loan Documents".  Hereinafter,
"Note",  "Loan Agreement",  "Deed of Trusts" and "Security Documents" shall mean
such documents as modified in the Modifications.)

         D.  Borrower  has  requested  that  Bank  modify  the Loan and the Loan
Documents as provided herein. Bank is willing to so modify the Loan and the Loan
Documents, subject to the terms and conditions herein.

AGREEMENT:

For good and valuable  consideration,  the receipt and  sufficiency of which are
hereby acknowledged, Borrower and Bank agree as follows:

1.       ACCURACY OF RECITALS.

Borrower acknowledges the accuracy of the Recitals.

2.       MODIFICATION OF LOAN DOCUMENTS.

         2.1  The Loan Documents are modified as follows:

                  2.1.1 The Conversion  Date of the Loan and the Note is changed
from November 26, 1995 to November 15, 1997.

                  2.1.2 Section 6.22.1 of the Loan Agreement is hereby  modified
in its entirety to read as follows:

         Tangible Net Worth in an amount not less than  $23,000,000.00 as of May
         31, 1995,  and increasing  thereafter  during each fiscal quarter (with
         the first such  fiscal  quarter  commencing  June 1, 1995) by an amount
         equal to twenty-five  percent (25%) of Borrower's net profit after tax,
         as shown on Borrower's quarterly financial statements delivered to Bank
         pursuant  to  Section  6.3.1.2  for the  immediately  preceding  fiscal
         quarter.

                  2.1.3 Section 6.22.2 of the Loan Agreement is hereby  modified
in its entirety to read as follows:

         A Debt to Tangible Net Worth Ratio of not more than 1.70 to 1.

                  2.1.4 Section 6.22.3 of the Loan Agreement is hereby  modified
in its entirety to read as follows:

         A Debt to Net Worth Ratio of not more than 1.25 to 1.

         2.2 Each of the Loan  Documents is modified to provide that it shall be
a default or an event of default  thereunder  if  Borrower  shall fail to comply
with  any of the  covenants  of  Borrower  herein  or if any  representation  or
warranty  by Borrower  herein or by any  guarantor  in any  related  Consent and
Agreement of Guarantor(s) is materially incomplete,  incorrect, or misleading as
of the date hereof.

         2.3 Each  reference in the Loan  Documents to any of the Loan Documents
shall be a reference to such document as modified herein.

3.  RATIFICATION OF LOAN DOCUMENTS AND COLLATERAL.

The Loan  Documents  are  ratified  and affirmed by Borrower and shall remain in
full force and effect as modified herein. Any property or rights to or interests
in property  granted as security in the Loan Documents  shall remain as security
for the Loan and the obligations of Borrower in the Loan Documents.


4.  BORROWER REPRESENTATIONS AND WARRANTIES.

Borrower represents and warrants to Bank:

         4.1 No default or event of default  under any of the Loan  Documents as
modified herein,  nor any event,  that, with the giving of notice or the passage
of time or both,  would be a  default  or an event  of  default  under  the Loan
Documents as modified herein has occurred and is continuing.

         4.2  There  has  been  no  material  adverse  change  in the  financial
condition  of Borrower or any other person whose  financial  statement  has been
delivered  to Bank in  connection  with the Loan from the most recent  financial
statement received by Bank.

         4.3 Each and all representations and warranties of Borrower in the Loan
Documents are accurate on the date hereof.

         4.4 Borrower has no claims,  counterclaims,  defenses, or set-offs with
respect to the Loan or the Loan Documents as modified herein.

         4.5 The Loan  Documents as modified  herein are the legal,  valid,  and
binding obligation of Borrower,  enforceable against Borrower in accordance with
their terms.

         4.6  Borrower  is validly  existing  under the laws of the State of its
formation or  organization  and has the requisite power and authority to execute
and deliver this Agreement and to perform the Loan Documents as modified herein.
The execution and delivery of this  Agreement  and the  performance  of the Loan
Documents as modified herein have been duly  authorized by all requisite  action
by or on behalf of Borrower. This Agreement has been duly executed and delivered
on behalf of Borrower.

5.  BORROWER COVENANTS.
Borrower covenants with Bank:

         5.1  Borrower  shall  execute,   deliver,  and  provide  to  Bank  such
additional agreements, documents, and instruments as reasonably required by Bank
to effectuate the intent of this Agreement.
         5.2 Borrower fully,  finally,  and forever releases and discharges Bank
and  its  successors,  assigns,  directors,  officers,  employees,  agents,  and
representatives  from any and all  actions,  causes of  action,  claims,  debts,
demands, liabilities, obligations, and suits, of whatever kind or nature, in law
or equity of Borrower,  whether now known or unknown to Borrower, (i) in respect
of the Loan, the Loan Documents,  or the actions or omissions of Bank in respect
of the Loan or the Loan Documents and (ii) arising from events  occurring  prior
to the date of this Agreement.
         5.3   Contemporaneously   with  the  execution  and  delivery  of  this
Agreement, Borrower has paid to Bank:

                  5.3.1 All accrued and unpaid  interest  under the Note and all
amounts,  other than interest and  principal,  due and payable by Borrower under
the Loan Documents as of the date hereof.

                  5.3.2  All  the  internal  and  external  costs  and  expenses
incurred  by  Bank  in  connection  with  this  Agreement  (including,   without
limitation,   inside  and  outside  attorneys,   appraisal,   appraisal  review,
processing, title, filing, and recording costs, expenses, and fees).

                  5.3.3 Loan commitment fees as follows:

                               (a) A  commitment  fee of one-half of one percent
(.5%) per annum of $15,000,000.00  of the Commitment Amount (i.e.,  $25,000.00),
for the time period from July 28, 1995 until November 26, 1995.

                               (b) A  commitment  fee of one-half of one percent
(.50%) per annum of the remaining $10,000,000.00 of the Commitment Amount (i.e.,
$16,666.00), for the time period from July 28, 1995 until November 26, 1995.

                               (c) A  commitment  fee of one-half of one percent
(.5%) per annum of $15,000,000.00  of the Commitment Amount (i.e.,  $71,875.00),
for the time period from  November 26, 1995 until  November  15, 1996.  Borrower
shall pay a commitment fee in the amount of $75,000.00 on or before November 15,
1996.

                               (d)      A commitment fee of one-quarter of one
percent  (.25%)  per annum of the  remaining  $10,000,000.00  of the  Commitment
Amount  (i.e.,  $23,959.00),  for the time period from  November  26, 1995 until
November  15,  1996.  Borrower  shall  pay a  commitment  fee in the  amount  of
$25,000.00 on or before November 15, 1996.

6.       EXECUTION AND DELIVERY OF AGREEMENT BY BANK.

Bank  shall  not be bound by this  Agreement  until  (i) Bank has  executed  and
delivered this Agreement,  (ii) Borrower has performed all of the obligations of
Borrower  under  this  Agreement  to be  performed  contemporaneously  with  the
execution and delivery of this Agreement,  (iii) each  guarantor(s) of the Loan,
if  any,  has  executed  and  delivered  to  Bank a  Consent  and  Agreement  of
Guarantor(s),  and (iv) if required by Bank,  Borrower and any guarantor(s) have
executed  and  delivered to Bank an  arbitration  resolution,  an  environmental
questionnaire, and an environmental certification and indemnity agreement.

7.       INTEGRATION, ENTIRE AGREEMENT, CHANGE, DISCHARGE, TERMINATION,
         OR WAIVER.

The Loan  Documents as modified  herein contain the complete  understanding  and
agreement  of Borrower and Bank in respect of the Loan and  supersede  all prior
representations,   warranties,  agreements,  arrangements,  understandings,  and
negotiations.  No  provision  of the Loan  Documents  as modified  herein may be
changed,  discharged,  supplemented,  terminated,  or waived except in a writing
signed by the parties thereto.

8.  BINDING EFFECT.

The Loan  Documents as modified  herein shall be binding upon and shall inure to
the  benefit of  Borrower  and Bank and their  successors  and  assigns  and the
executors, legal administrators,  personal representatives, heirs, devisees, and
beneficiaries of Borrower, provided, however, Borrower may not assign any of its
right  or  delegate  any of its  obligation  under  the Loan  Documents  and any
purported assignment or delegation shall be void.

9.       CHOICE OF LAW.

This Agreement shall be governed by and construed in accordance with the laws of
the State of Arizona, without giving effect to conflicts of law principles.

10.  COUNTERPART EXECUTION.

This Agreement may be executed in one or more counterparts,  each of which shall
be deemed an original and all of which  together  shall  constitute  one and the
same  document.  Signature  pages  may be  detached  from the  counterparts  and
attached to a single copy of this Agreement to physically form one document.

DATED as of the date first above stated.



                                     MILBURN INVESTMENTS, INC.,
                                     a Texas corporation       
                                                               
                                                               
                                                               
                                     By: /s/ Kenda B. Gonzales
                                         --------------------------------------
                                     Name:   Kenda B. Gonzales
                                           ------------------------------------
                                     Title:  Treasurer
                                            -----------------------------------
                                                 BORROWER



                                     BANK ONE, ARIZONA, NA,         
                                     a national banking association 
                                                                    
                                                                    
                                                                    
                                     By: /s/ Rhonda R. Williams
                                         --------------------------------------
                                     Name:   Rhonda R. Williams
                                           ------------------------------------
                                     Title:  Assistant Vice President
                                            -----------------------------------
                                                                           BANK