The original Boss 429 parts are very hard to find, but a Boss 429 can be had. John Kaase builds the heads and intakes and other parts for the Boss. These parts are built to be used on any 429, 460 or larger stock and aftermarket blocks. They use standard ford big block head gaskets and are an improvement over the original heads, which used a special block. They can be built out to at least 600 cu.in. So yes you can have a Boss, and yes they make big H.P.