5WINDOWJOHN,

Are you referring to a GMC 2.5 ton truck (1947, New Design)?

Here are the 1947 Chevrolet Advance-Design models.

If you are referring to the A-D cab, it is the same for all sizes of Chevrolet trucks. The smaller fenders and the larger fender will bolt onto that cab.

Fenders looking funny might just be in the eye of the viewer/beholder. What size wheels/tires will you be using (1/2 ton 15"/16" wheels or bigger truck 20" wheels)? Match the fenders to the wheels.