could you be more spicific about this comment please"The LS6 and turbos are fine but you will have to run in plain old Alt " can i run any(aftermarket) turbo charged & EFI engine..the 2012 rule book isn,t all that clear to me on sedans....it says "cbfalt,cfalt,cbgalt,cgalt,and so on..infront of all these it say "coupe".......again thx