The height of the 3/4 ton frame rail is less than the height of the 1/2 ton frame rail. The tank mounts fit into the frame rail. I tried to mount a 1/2 ton tank to my 3/4 ton truck. Don't fit.
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'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
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