Don't know anything about code or how hard this would be to model, but it seems like an easy one to me. No putting together a brand new airplane here.
Just take the P-47D-25 (or D-40 if you want to count all the field modified dorsal fins) airframe and substitute the P-47N engine. Everything else (as far as gameplay is concerned) seems identical, other than performance.
I know Yucca has asked for it before, and I know "there will be no new planes until CT is finished". But this wouldn't take very long to put together would it? Find a generic 56th skin for the default and voila. Then we get to make all those cool 56th skins... I know only 150 were built, but then that matches Ta-152 production as well...