The Stovebolt Site Forums The Parking Lot '60-'66 Trucks 64 grille on a 62 truck?

From a post on another forum:

"all the grilles 60-66 chev/gmc 1/2 ton to 40 series use the same 2 upper outside bolt holes.
the breakdown should be:
60-66 gmc, 60-63 chev use the same 4 holes.
64-65-66 chev use the same 3 holes.
the big truck grilles can be modified to fit:
the 50-80 series chev use a flat: 90 degree angle grille support, so in order to utilize one of these grilles the bracket from a 1/2 ton-40 series grille must be installed.
the 60-63 chev grille will fit better if it is sectioned about an inch, however I do have a pic of a direct bolt on as well.
the 64-66 chev grille will fit if the CHEVROLET letters are removed from the top.
the gmc grilles are exactly the same as the light truck, except for the mounting bracket.
also, the 1/2 ton to 40 series grille support changed when gm switched away from the x frame in 63, so a 60-62 chev and gmc grille support will not work on a truck with a 63-66 frame without a little modification."

So, in short, yes (AFAIK). Basically, the '60-63 will have a couple extra bolts (one on each side) that the '64-66 doesn't.