Heres my story on the 250-216 swap. My '37 didn't have any drive train so I was starting out fresh never seeing a engine in the stock location. I placed the radiator and support on the frame then went about setting the engine in place. Once it was in place, I set the cab on only to find out the firewall hit the back of the engine. I moved the radiator forward in the frame, moved the whole engine forward some, and still needed to move the fire wall back a little. I know what the books say, but I still believe the engine is longer.
Joe