no the 37 coupe is not interchangable with the 34. The body and chassis are completely different. There have been 37 Coupes converted to 34 coupes with chassis fab work, THIS IS NOT LEGAL! By the time you do it all, change the rear bars and convert the doors to suicide style and then buy a 34 body it is not worth it.
Dennis Knox
Buckeye Legends
330-310-9212