Another type of insulator, or issolator material often used on heavy dump bodies is a rubber strip of about 5/16-3/8" x 3" of 90 durometer rubber. It's available from industrial supply houses. Old rubber belting could be used also for your project.

1953 Chevy 5-window 3100
In the Stovebolt Gallery
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Dave
Engine & Driveline Moderator

If you can't make seventy by an easy road, don't go. ~~ Mark Twain