My first choice would be to leave the cab on the original frame, and modify as necessary. I'm just not a big fan of four wheel, non-power drum brakes. I remember switching my first car from this to power front disc/rear drum and the drastic improvement it made. But that was a pretty simple, bolt on process, even 30 years ago. If I were to keep the original drums all around, I would still need newer wheels. It appears that the standard GM dually wheels have too much offset for the front, and not large enough diameter for the rear. Has anyone tried railroad wheels? They are used on single wheel one tons to "narrow" the track of the truck to fit the rails, and look to have a similiar offset.
