Have you tried to mock up the engine in the car yet? A 440 is a very tight fit in an early A, I had a 440 setting my car and there is less than 1 1/2" between the heads and the shock towers which makes for fitting headers a very difficult process unless you relocate the shock towers, and even then, fenderwell headers are your only option. You also need to pie cut the tranny tunnel to clear the bell housing.