Quoted from hoov:I would triple-thick your glass IMHO only because you say "it's starting to bubble". That tells me it has de-laminated and will probably get worse. A scratch or nick in the paint doesn't qualify for sealing but bubbling does. By sealing the glass you will prevent any future damage if done correctly.
This is great information and I've saved it. I want to TT my backglasses to protect them but how do you get a United woodrail backglass out of the backbox? It doesn't have the lever that holds the board with workings in like the wedgeheads do.