I have seen/run the rivet presses used on GM trucks in past. In plant we set a cold rivet in the holes which were loose fit, then lowered a large c'clamp looking device over it and squeezed the trigger. A slow moving piston with dip in it fit over the head and pressed the rivet into another dipped out anvil that was stationary. Pressed rivet tight and expanded it in hole at same time, that's why they are hard to get out and need driving with a punch even w/out heads on. Most books I have read reccommend using next biggest diameter bolt to replace, 7/16" in this case, don't know why. I have not done that and used 3/8" grade eights, many times "borrowed" from the plant that had washer heads and nuts, mostly lock nuts. Now they are metric and DO require me to drill larger to use...I mean "test"! The presses used up to 92 were there from the 20's, so they did it the same for long time, don't know how you could copy that. Now days they are mostly welded up frames, some bolts, but up to the 98 models they still had some of same rivets, just put in at frame factory then.
