Think about it, they are like parts of an erector set, have one basic chassis truck make any model you like.
The original pipeline truck (later M756A2) was actually only a bed assembly with all the goodies, to be swapped with a cargo bed or any other model for that matter as needed. My pipeline truck bed was a separate unit, with its own data tags, the HIAB crane was the same, to be used on any M35 type chassis, it too has its own data tags, so what you see in the avatar is my own version of what I consider the ideal for me....still an all military version of the deuce, but no particular model number.
900 or 1100 tires, with or without winch, soft or hard top, etc, all "legal" bolt-on swaps with no change in model number....