I'd think getting the heads off wouldn't be a problem. Mines a V10, and there should looks like there's plenty of room.
I don't envy the man who's gonna lift that iron head out through the wheelwell though.
It's not gonna be worth it to try to fix a broken iron 460 head. Replace it.
I think Edelbrock might make an alluminum hiperf head, here's a link Edelbrock.com - Cylinder Head - Ford - Big Block - Performer RPM 460
it says 67 to 87, might be worth a phone call for fitment though. I bet a pair of those and a matching manifold would add 150hp to that 460!
Heck, you could drop an oil can thru those intake ports, arrrrg arrrg arrrg!!!