Pull them off on a hot day in the afternoon if you can, having everything nice and warm/hot makes it easier. X3 on the adhesive remover, advance and other parts places carry it in a gold/tan pint can.
A hair dryer and 30lb mono worked on the badges. The 4x4 stickers just peel off with heat. Oops or GooGone for adhesive. But anything stuck to GM clearcoat actually sinks in a little and leaves a ridge. You can't see it, but it's enough to catch dust and show an outline of what's been taken off. It needs to be smoothed. White (fine) compound and a lot of rubbing wasn't enough so I had a body shop polish it out.