With the frame swap, you have to deal with changing body mounts, frame length, possible wheelbase issues, brake master cylinder mounting, plus the axle width issue. Using the stock frame takes out virually all of that, exept for the axle width and trandfer case crossmember issue. The cleanest conversion I've seen using a Task Force body truck used the stock frame modified to take the steering boxe, trannsfer case crossmember, and axles from a '70s model GM truck. It looked almost factory.
