I just did this on a Grand Prix. I had to use an angle grinder to grind the heads off,dont worry about damageing the ball joit,thats going in the trash anyway.Now on the Grand Prix a Punch and hand held sledge wouldn't work after grinding off the heads! Use this,step if you can't hammer them out (after grinding). I dimpled the center of the ground down rivots with a dremmel. I then progressivly drilled through the rivots (use plenty of oil,it will keep your drill bits cool and sharp).Use a slightly larger drill each time,eventualley the remainder of the rivots will fall apart or come out. If you still can't get them out,you may have to grind the bottom of the rivots off too. Use an old bolt to gauge the size and length you'll need.Now go to Home Depo and use High grade steel bolts from their bolt section,Look for a drawer chest with metrick bolts,they are high grade steel (allso try and find lock nuts or use lock tite,if you can't find those).Otherwise,you can get bolts from the wrecking yard.
[This message has been edited by James Bond 007 (edited 07-12-2013).]