I have that same thing in the plans for the back of my 89.
A local street rod shop used the spray on stuff(comes with its own gun) on the underside and all of the interior metal on allot of the street rods they built.The stuff is as tough as nails and actually sound deadens the metal and seals out moisture very well.....

........Wookee


Its a "Van Thing"
A life style you have to LIVE to understand!

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Vintage Chevy Van Club