CPPA Slant six to RB motor mounts and CPPA headers...

Not sure about the mount question. Are you using a b or rb? I have the CPPA headers on my b engine in a 69 B'cuda with a 4 spd.(factory bb k-frame) They fit but are very tight in a couple spots, nothing a little massage won't cure. Starter will be trapped...so buy a good one!!