400 motor parts

I have a 400 in my new swinger… it’s already built but doesn’t have aluminum heads. Honestly I don’t know anything about the internals of the engine either, besides it all being newly rebuilt and never started, it has the XE274H comp cam in it, the guy who was building the car passed away.

Do the Aluminum SM CNC heads fit on the 400 blocks as well? How about the roller rockers?

Anything else I should look for on Black Friday?

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