There were three different front fenders:
* 1/2 and 3/4 ton used one size
* one ton and 1-1/2 tons with 7.50-20 tires and smaller used a second size
* and 1-1/2 ton with larger tires and two-tons used the third size

The way to distinguish between the three is the size of the wheel opening, with the 1/2 and 3/4 ton trucks having the smallest wheel opening. The third type (1-1/2-2-ton) is easy to distinguish from the front because it looks like the bottom almost comes to a point where it meets the grille. If you look through some of the pictures in the gallery, you'll see what I mean.

I've seen trucks where someone used 2-ton fenders on a 1/2 ton pickup and the tires looked waaaaaay too small and it looked terrible.

Bob