My dad and brother just bought a 52 more door nice solid car but no motor. The question is will a 390/c6 fit without complete reconstruction?
A 5.0 with an AOD or C4 is a much better and easier fit:http://www.butchscoolstuff.com/store/cart.php?m=product_detail&p=15 Note that there are two kits one with a 15" measurement and one a 17" it shows how to pick the correct one.Also headers are a no brainer,if you were working with a '54 or later then the 390/C6 would work OK.However the stock '52 rear can handle a 302/5.0 with an automatic but if you go the 390 the torque increase will call for a rear end swap.The size of the C6 will probably call for tunnel mods and mounting issues in a '52-'53 car.
289/302 with a c4 or AOD was the original plan but I just picked up a 390 c6 for cheap so it may have to wait for another project
Anything can be made to fit, it just depends on how much ''reconstruction" your willing to do or capable of.