Welcome aboard the Stovebolt train. Many people will tell you that the GMC's are superior and in some ways I guess they are. The 228 GMC was purposely designed as a truck engine. It has full oil pressure to the insert rod bearings, heavier, beefier rods and a higher nickle content in the block. The GMC boys can list more things that make it better. The 216 is a car engine, though it made its way into millions of Chevy trucks and I love mine. Have you checked out oldgmctrucks.com? Lots of great info over there and an active forum. You can probably put your 51 Chevy cab/body on the GMC chassis. The radiator will probably have to go forward approx 1-2". Maybe Oldsub or one of the other GMC knowledgeables will chime in. Good Luck!!

Professional Novice