I would keep it open to wet or dry sumps, carb or injection to be able to allow many mod and stock car guys to go purchase a 3-5 thousand dollar roller and go compete. Possibly require weight rule for the dry/inj. guys over the other. Also, the 16 square wing is produced by the hundreds in PA for the 358 class by many different manufacturers, and any builder out here would be able to produce them easily if there is a potential market. Just keep it simple.