I have also done this on my vintage license plates. Instead of sticking the sticker to them when in use I just put a magnet on the sticker when I get it, and then put it on the plate when needed. This way you don't get a big stack of stickers on your nice plates, and it looks cleaner, like day 1 when the plates were new. I have also done it with vintage stickers that I don't want to waste.
As far as your sticker Mike. I would make a couple of them. The new cars these magnets work on, very thin paint little clear. It may take a little thicker magnet to have it stick well on your tail panel. I would also have a copy made to go into a binder of all your docs, and rest-o pics.
Great find, wish I could find something from my dealer, License frame , sticker , anything. I was lucky to negotiate the key fob I suppose...