I did this on my e46 318 last week. Car is parked in the street and it was a warm day. Cotton thread to cut through the residue of each emblem by getting behind the badges. Picked the residue with my fingers to remove. Some, just a little, t-cut scratch remover, the mild stuff not the real t-cut, to remove the last of the residue. Must say, it took me a whole 10 minutes with excellent results.