I have two AVI type stickers, Peach Pass and one for my work garage.
It took some experimentation, but as a couple of other people already note (and I thought I was going to be the first), I have slide each of them under the black plastic housing of the rear view mirror. I have NOT removed the backing for the sticky side. I think they will stay, or I may use a small piece of double stick tape.
I have tested each, they both work great now. I can post or send pics if anyone needs them.
The peach pass sticker is long and thin, that one is almost completely hidden under the plastic housing.
The work garage AVA is credit card sized and the main part is under the housing (and pushed up under the fabric above) and about 1/3 is exposed.
But it all works!
It would have been very helpful if Tesla had given us easier access to under the nose or the front part of the roof (the 7" wide or so strip that runs between the windshield and the pano roof).