If you're running in SCCA, you might want to pick a class first and see what the rules allow. Supercoupes are, depending on their mods, eligible for F Stock, E Street Prepared, Street Modified, and C Prepared. How serious do you want to get? Will you use street tires or R-comps? I autocross frequently and ran my SC for a year with SCCA. I'd be happy to help, but the more info you provide, the better we can all help.