Everyone, the 413 in my 71 short-wide bed shot craps so I'm looking to drop in a good-running mid-70s cast crank 440/727. I would like to run a modest cam and raise the compression a bit while motor is out of truck. I have 452s on it now. Is there a factory head that would increase the compression to near 9.1? Can i mill my 452s enough to get 8.5 without having significant valvetrain and intake manifold issues? I don't want o spend a fortune on the truck, just put it back together for now while i finish the new 360/A500 swap in my 77 shortbed. any suggestions are welcome! Thanks, JP in the land of oz.