Are you swapping big inch to little inch?

I’m helping my Dad convert his hot 440 / auto 1970 Cuda to a 360 magnum short block topped with X-heads and a 6 barrel drive brake and Fi Tech carbs. Also, I’m giving him the Tremec 5 speed that is in my Cuda.

He drove a 1970 Cuda 340 / 4 speed when he was in H.S. in 1971. He just wants his car to be more like that one. He’s in his 70’s and isn’t concerned with the big power that the 440 makes. The price of gas isn’t the main driver. He wants a milder engine. If his 440 was OEM specs and had highway gears he may have not really had the urge.