Passenger window has come off track - window repair guy says his company wont allow him to use silicone on the window to reseat it (problem with the tabs) - and the adhesive they use wont stick to silicone which is on the window so only option is to replace whole window. This sounds like a scam to me. Question is -cant I just reseat and re silicone the window myself or is this a process that is too involved and should be done by a auto glass company?