That 67 head has the same ports, and obviously it bolts up, but the combustion chamber design is completely different (small closed chambers). I wouldn't spend a nickel on a carb upgrade when I'm running a different compression ratio on each bank of cylinders. How the heck are you going to tune that? I would also suggest that a 750 is a little more carb than you need on a small port, small displacement V8. The factory solution was a 450cfm Carter AFB, and even that motor had higher compression and a more radical cam than you have. Sure, you could make it work, but at least fix the heads first.
