Hi Josh; I'm no expert but I do know the '52 head (15 bolt) won't fit a '54 block (18 bolt).
If your older engine is good, I'd keep it for now unless you plan on doing a correct restoration. If you just want a driver, why not keep the ol' splasher for now (a lot of guys here have them and love them). It'll do a good job for you if operated within reason. Then, you could keep your eye out for a correct '54 engine and when that comes along make the swap.
Good luck with your project, whatever you decide to do.
