440 vs. stroker 408 build?
I do not believe there will be a problem with the '74 swinger in the engine swap. Earlier A bodies have the smaller engine compartment.
Handling aside, the 440 is the way to go for brute torque and easy HP to weight ratio in the favor of smoking tires and quick times.
Your right, it is the easy way to add mega power under the hood. The 440 weighs in a bit more than the 383 - 400 because of the extra height of the engine. With aluminum parts and headers, the weight drops alot and down to a much better level to deal with. Aluminum heads would be even better, but do cost additional cash that could be useful elsewhere.......for now. (?)
Do not exceed 9.5-1 comp. ratio with the open chamber heads. Reason being is a set of closed chambers or milled iron heads will raise it and pump gas could be a pain to run. Closed aluminum heads would be fine.
Even a mild build of 1 hp per cube would be great. The car will be a ton of fun with all the torque the 440 makes.