I have a white exterior and I received my red HOV stickers weeks ago. I do plan to wrap the entire car in Xpel Stealth (matte). However, I refuse to put these horrible looking stickers on the car (before or after the Xpel). So I wanted to do the same thing. In fact I thought of this idea long before I saw this post. Put the HOV stickers on thin magnetic sheet. I'm also planning on dropping the bumpers or inside wheel well plastic and epoxy some neodymium magnets I have to the back side of the bumper. This should allow the stickers to remain on while driving to the plastic bumper. Yet I can remove them after the drive and put them in the glove box afterwards.