Eighth Amendment to Revolving Credit Promissory Note between Perma-Bilt and Zenith National Insurance Corp.

Exhibit 10.20

EIGHTH
AMENDMENT
TO
REVOLVING CREDIT PROMISSORY NOTE

        1.    Reference is made to that Revolving Credit Promissory Note dated April 5, 1993 made and delivered by Perma-Bilt, a Nevada Corporation, a Nevada corporation, to Zenith National Insurance Corp., a Delaware corporation, the original principal amount and original Maturity Date of which were Eleven Million Dollars and December 31, 1996, respectively. Pursuant to an Amendment dated November 10, 1995, a Second Amendment dated June 26, 1996, a Third Amendment dated as of July 28, 1998, a Fourth Amendment dated as of December 8, 1998, a Fifth Amendment dated as of December 2, 1999, a Sixth Amendment dated as of December 11, 2000, and a Seventh Amendment dated as of December 11, 2001, the principal amount has been increased to Forty Five Million Dollars and the Maturity Date has been extended to December 31, 2002. Reference herein to the "Note" refers to the Revolving Credit Promissory Note, as so amended.

        2.    The Note is hereby further amended by adding the following to the end of the second paragraph:

The foregoing interest rate only applies to borrowings outstanding on or before May 31, 2002. The interest rate on borrowings that are outstanding on or after June 1, 2002 shall be ten per cent (10%) per annum.

        3.    Except for the specific modification, as set forth herein, the undersigned expressly reaffirm the terms and conditions of the Note.

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