bOSS 302 IS ACTUALLY A 4 BOLT MAIN 302 WITH CLEAVLAND HEADS. IF YOU WANT TO MAKE YOUR OWN BOSS YOU NEED TO DO SOME HEAD MODIFICATIONS BUT IT IS NOT HARD, I BUILT ONE FOR A FRIEND AND WORKDED OUT REALLY GOOD.
YOU SHOULD FIND EVERY THING YOU NEED 2 KNOW HERE
http://tomsmustangbarn.tripod.com/sbossbuild.htm