Welcome, the cab and interior on the 1.5 ton is the same as the 1/2 ton, the big truck has bigger fenders, a different steering column and column drop, and the pickup has the gas tank at the rear rather than under the seat. Brake linings and other truck-specific parts show up on e-bay. Your truck could have had 600/20 or 650/20 tires originally, I got mine from Lucas. What wheelbase is your truck? ..B.