The lifter oil passages will have to be blocked, and you will have to use a dummy cam bearing or some kind of a block in the #4 cam journal, otherwise any 427 block will work. I don't know if a Genesis block can be drilled for the oil drain passages, but my Pond aluminum block has them, so a Pond cast iron block would probably have that as an option also. But you will never see the external oil drains with the engine in the car, and some people think they work better than the factory drains. I wouldn't rule them out...
