Yep, the rubber mounts are what I was mainly talking about. The metal mounting ears have an larger elongated hole for '81 and up, the rubber part fits in there. I did not think you would want to remove the ears off the frame and mount your '79 ears. The mounts are in the same place, so just use the rubber from the '86 and your body will bolt right on. The parking break cable from the '86 will need to stay as well, it will snap right into the '79 pedal assembly. May have to mess with the fuel sender wiring, too. Can't think of any other issues.