Are all single cabs from 1994-2002 the same? As far as frames, are all the 135" wheelbase(regular cab dually) frames the same from 2WD/4WD?

Got a 1998 C&C 138" wheelbase, 2WD, weighing my options on possibly swapping the cab onto a 135" wheelbase frame. Just looking to get some basic knowledge on cab and frame differneces. Thanks.