[FFR428]

The 428 might be decent depending on what parts it has. You will be starting with at least a 4.13 bore depending on what bore is at now. Being it's complete and untouched I'd guess it's still a std bore block maybe. Check out the heads and intake and have a closer look at the internals. If it looks good you have a nice 428 to rebuild and can be done fairly cheap using existing parts. New cam/lifters of course and the normal rebuild parts would be about the same as the 390. Just something to think about...G.