Had a little time yesterday to do some cosmetic work on the SLE. Went to remove the dealer sticker and found the bums had PAINTED their info on using a stencil. I used carburetor cleaner on a terrycloth towel to rub it off a little at a time. As long as the urethane clearcoat underneath is in good condition (no scratches) this can work. If there had been any cracks or scratches in the urethane clearcoat, the carb cleaner (which is really just lacquer thinner) probably would have played havoc with the basecoat. But it worked fine.
When I got rid of that, I carefully used my heat gun and a dull putty knife (ran it on the wire brush wheel) to remove the plastic PONTIAC badge from the middle of the trunk. I only cut through the foam layer which left a layer of foam with adhesive on the car. I used my fingernail and PB penetrating oil to tease off the remaining foam and adhesive. Back end looks pretty clean now. All I have to do is polish and wax.