I read this elsewhere :
PersonOne wrote:The only issue is removing the residue glue from the old stickers... What a workout, I used Goo Gone, Alcohol and a lot of elbow grease but I got it all out.
Somebody Else wrote:Removing the old stickers is trivial, if you briefly hit them with a heat gun. In my case, both layers came off at once, without activating the voiding on the sticker(s). There was a little residue that came off easily with a solvent based adhesive remover. I used a 3M product, but goo-gone will probably work just fine.
I realize most folks don't have a heat gun, but a handheld hair dryer will get you most of the way, with a little more patience.
Another Person Said wrote:I put my red decals right on top of the old ones, as suggested in the literature provided with the red decals. It was not difficult. If you choose to remove the old ones, be very careful when using heat or solvents to remove the decals: it is likely very easy to damage the painted plastic fenders and bumpers. Goo-Gone has a strong solvent in it that may attack the paint, but a very brief exposure may not cause any damage.