I broke the upper shock mount on the rear driver side of my 86. Upon finding a replacement I took a air chisel to the top of the rivets to remove the bracket. Much to my dismay when I got the bracket off I still could not remove the rivets. I can not get at them from above to drive them out, nor from the bottom due to the gas tank and other cross members that are also riveted on. I know that a number of you have done this before, and I'm wondering how you went about it. I tried to tighten a bench clamp on them to drive them out, but that didn't even budge them. I drilled a hole in the frame for now, but I figure there is a reason gm engineers put the bracket where they did, and I would like to get it back on. Thanks for any idea or techniques that you might have.