The prep of the window and bracket is very important to insuring the brackets stay attached to the windshield. I had to re-do mine twice, after i was dis-pleased with the dealers install.
You'll need; 3M Extra Strength Automotive Tape (comes with red backing), Adhesive Promoter and a hair dryer.
1. Clean the windshield surface and bracket, where tape will go, with alcohol.
2. Apply Adhesive Promoter to both the windshield and bracket.
3. Warm up the bracket with hairdryer...nice and warm too and apply the 3M automotive tape covering entire bracket surface that will go against windshield. Apply pressure to tape, I used some small automotive clothes pin style clamps. Making sure the tape got stuck on there real good.
4. Warm up the windshield with hairdryer, nice and warm too.
5. Peel off red backing on tape and apply bracket to windshield at exact spot you want it. Apply pressure. I rigged a long pole, wedged against garage ceiling and bracket with a block of wood on bracket to insure even pressure and let it sit overnight. Keeping constant pressure on the bracket to insure tape got stuck on real good.
Since going thru this process over a year ago, I've not had a single problem with the brackets trying to lift off the windshield and its been out in direct sunlight over the summer where I know the surface temp was up there.
It's all in the prepping of the windshield and brackets and the dealers won't take the time needed to do it right. We will though!!
IF MY CAR WENT AS FAST AS THE MONEY I SPEND ON IT, I'D WIN EVERY RACE