I'm currently prepping mine, I have used a special rubber wheel that "erases" the glue, but it's slow, and they are expensive. I'm replacing the front grille header, and the later model letters are glued on, not fastened. Less holes to fill, good, but more glue.
The paint will scar unless you are very careful. Frequently, the glue used will pull off the paint, especially a repaint. Whatever tool you use may also mark it if you attempt to lever at all.
I'm interested in whatever will dissolve the glue, too, but I'm thinking it would probably be close to an atomic molecular bond dissolver, which is probably a hazmat issue. I'll keep scraping and sanding until then.