what i've been doing the past coupe of years is *not* using the sticker's adhesive backing to affix to the window. i affix the permit to a piece of plastic wrap, basically to negate the adhesive. then i just use two small pieces of scotch tape to mount the permit. takes about 2 seconds to remove, yet doesn't look any different than if it were "stickered" to the glass (in case you're worried about permit theft).