47 and 48 use the 3 bar grille with the much more pronounced uprights, as well as a completely different front bumper. 49-55.1 are all the same grille and share the front bumper with 47-55.1 chevy trucks. This is for 1/2 through 1 ton trucks of course.


1956 GMC 100 NAPCO Deluxe
1955.1 Chevy 3600 NAPCO
1954 Chevy 3600 NAPCO