318s are ok but will never make torque like a 440. When you drive a 318 car that can pull off mid 14s its cool, but a stock HP 440 will do the same thing and the torque that the 440 makes just really makes the car a pleasure to drive, even with highway gears.

Its a very straight forward swap in a B body. The 440 out of that car will go right in with a big block 727. You wont need anything other than motor mounts if you want to replace them. It will require some exhaust modification, obviously, but really thats about it. Apparently you have to modify the hot wire to the coil to be longer, but I didn't have to in my Satellite.

It required more work to switch my car to the 727, as I needed a new throttle pressure linkage and shift linkage. You wont need a new shift linkage though since your car has a 727 already and the throttle pressure linkage in that Dodge should work in your car I believe, might have to double check on that though.