The frames are the same gauge and shape but the GMC has the front engine mount a bit further forward to accommodate the longer engine and more forward radiator mount. The body work is the same except for said radiator mount and the front of the hood. The GMC fenders will have parking light holes; the Chevy has them in the grille. The dash will have General Motors Truck on the stainless accent strip instead of Chevrolet. That's about it.
