knock out the center of the rivet, then drill it out. remove the linkage from the handle, and remove the handle. to reinstall, you can use bolts, like stated above, or you can rivet them back in. it takes a special 1/4" self splitting rivet, and a "big daddy" rivet gun.
Be sure to put some duct tape with a small bit of cardboard behind it just bleow the handle to prevent the rivit gun from scratching your paint. Ive seen it happen before...
You do have to drill them out. I like the tip on bolting them back on. On my 89, I riveted the replacements on. Unfortunately, they were pieces of crap and I had to borrow the rivet gun and do it all over again. Do the bolts.