I used a heat gun and some GoofOff and it worked great! Just sweep the heat gun in circular motions around the lettering for about 30-40 seconds and then using something plastic with a stiff and thin edge, scrape the lettering off. What will happen often is the gel-like letting will flake off from the adhesive, leaving all the adhesive on the car. You need to press pretty hard to get it to come off all the way, and then go over it with the goof off once you removed as much as you can. You'll have to be very liberal with the goof off, so buy a whole new can to be safe. My paint was fine, and wasn't harmed by the goof off or the heat gun. I did clean it and wax the area shortly afterwards though. I also recommend wearing gloves, since the doors will get very very hot from the heat gun and you will burn yourself.