Can you email pictures. Look on the back of the glove box lid for the "GMC PARTS Identification" tag. It will tell what series it is along with eng. type, trans. type, rear axle type etc. Could also be a 3 ton. or 3 1/2 ton. Depends on the series. 400 series 2.5 ton, 450 series 3 ton, and 470 series 3 1/2 ton. If it is indeed a 54 model, and is a 300 series 2.5 ton, it won't have a 302 in it. It will have a 270 engine. 1954 450, & 470 series trucks had the 302.
