They are, but supposed to be able to be installed in glass also. Thin glass, it would be easy. The thickness of these is what's giving me the problem atm. Nothing I'm not certain I can't solve.
I'll post more of the what the actual problem is soon, maybe you guys can give some ideas.
Either Monday evening or Tuesday, I will post more. I'm preparing to drive to dallas to pick up a car (righting the wrong I made when I sold my 50th anniversary Mustang, found one with 400 mi and still 2 years warranty left), prepare the wife's car for a trip to TN the week after. So I don't have but a day to a day and a half. But stay tuned. I gotta get this done. I'll try to stay focused on this before I go back to the front end lol