I considered this setup when doing my 350 swap, and was told that a new bellhousing adapter was necessary for the conversion to AX-15/Chevy 350. I wound up going a different route choosing an NV4500 behind a 350.
As for the radiator, I have the aluminum 4 core BeCool radiator and electric fan combo and still get a little hot when crawling. I wouldn't think a stock radiator would cut it. You might be able to get by with an electric fan on the front of the radiator, and a mechanical fan on the engine side. Good Luck!!