I used a World block to build the 540 Hemi in my 70 Cuda. TTI headers fit good although I think they hang too low on the passenger side. The Edelbrock/MP heads and stock valve covers clear the passenger fender well. But it is very close. I used a stock repop K member and steering with a stock 6 qt oil pan, but back it up with the Accusump.

Is this a track only project? My engine only made 650HP during break-in and it is an absolute hand full on the street with 295 drag radials and Cal-Tracs. I don't know what you are planning for rear suspension, but I can't even imagine what hooking up your monster with a stick will be like. And trying to steer it with one hand. Your buddy is BRAVE! Good luck.