How do you remove AR from lenses?

[AR Coating Lab]

We use ammonium hydrogen difluoride, 95% pure, tech grade (CAS:1341-49-7). We make a solution that is about 9 parts water and 1 part ammonium hydrogen difluoride. If you use too much of the chemical it's not a problem because only so much of it will dissolve at once. As it is used up the rest will dissolve so if you see undissolved crystals at the bottom that's okay. You immerse the lens into this solution and watch it carefully. You will see the AR coming off. Then you rinse the lens off with water and dry it with kleenex. You should wear gloves when stripping lenses. Old poly and high index lenses are the hardest to strip. Glass will sometimes be cloudy afterwards, but you can buff that out.
BPI sells a kit with their own chemical and a container to strip lenses in.

[AR Coating Lab]

Trivex, high index Transitions lenses and Signet Armorlite Poly lenses seem to be impossible to strip without clouding the cx side hardcoat.