KB5 FENDERS

are the front fenders on a 1/2 ton the same as on a 1 ton

No.

K, KB-1 2, 3, are the same, K, KB-5 have a bigger wheel cut out. all will bolt up, if you want to put smaller tires on your KB-5 you can put on the KB-1, 2, 3 fenders for smaller cut out around your smaller tires

You say one ton. Kb5 is usually called a 1.5 ton.
Anyway, fenders are different.

ok,so the cab is the same,but the fender wheel opening is not.

I think I remember hearing that it is a case just like the smaller L trucks and Larger ones, Cab is basically the same(floors are slightly different) and they set up higher so fenders were longer/bigger to handle the bigger rims/tires required for the weight. What size are your wheels? If 16" then the smaller fenders should work fine, if 20" probably need the larger fenders or a set of smaller wheels to fit. Just my thoughts, others with more knowledge will speak up.

not sure what i want to do yet.4 wheel drive or street rod it.i like big trucks so i think i might 4x4 it with 3/4 ton axles.if i can find a transfer case out of a 73 ford f250 i can keep the flathead 6 and 4sp trans.