I have a 77 CVX 20 with the stock 460 in it. I want to repower her from 330hp to the 400-500 range but the engine hatch is very narrow and after market high flow exhaust manifolds for 460 are hard to find that would fit in my compartment. As opposed to rebuilding the 460 i've thought of dropping in a newer 502 or some other chevy that is powerful enough. Other then the motor mounts, exhaust manifolds, and bell housing what all would be involved in the swap. Has anybody ever put a chevy in one of these hulls ? Any and all advice will be appriciated. Thanks