My boss has a 1931 Chevrolet roadster that needs a total engine rebuild.  I'm looking into possible options to get the car back on the road again.  Best case scenario would be to find a good used engine that we could install in the car, so I'm trying to find out if it has to be a 1931 engine, or if there are any other years that would work.  I've searched all over and can't find any information about what year engines will interchange within the early stovebolt designs.  All I have been able to learn is that 1937 and newer are very different and won't work without major modifications, which we don't want to do.  Any information would be greatly appreciated.

Jeff