I installed the molded gaskets I purchased from Chevs of the 40's and they were very close to the same thickness as the rubber gaskets that were between the fenders and cab when I removed the fenders. I had a similar problem but maybe not as severe as you describe. I used larger diameter washers to help spread the load and it seemed to work out ok. I might suggest that you back off the torque so as to not compress the rubber as much.

Ron - - Dusty53
1954 Chevy 3604
In the Gallery Forum
"You can't dance with the Devil and then wonder why you're still in Hell."
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