1992 Shortbed extended cab 1500 series 1/2 ton., Wheelbase-141.4", width- 2wd-76.8, 4x4-77.1. I don't have the exact frame dimensions handy, but I can tell you that the frame is rather wide at the center, and the rear section has a definite taper to it, narroing to approx 34" at the bumper mounts. Think of it a the reverse of the '47-'54 3100 trucks.
