I usually like to add a little extra clear so it looks like a 3/16" gap at the primer stage would be about right.
Thanks for the tip on MarGlas. I've had good success in similar applications using West Systems and Milled Fiberglass mixed to real thick consistency. It's real tough after it cures and you can sand it to a razors edge!
FFR 3135, 306 TFS EFI, Baer 13" brakes. Over 23,700 miles & 482 engine hours since May 2003.
RCR GT-40, 418 stroker, ZF