I am looking at a tinted rear glass back glass for my 55 Ford. The problem is that it has a deep scatch in it from being in a salvage yard for many years. My question is as follows. How well does the #40030 deep scatch buffing kit work. Does this kit work well on a back glass? How deep can the scatch be? I would gladly order this kit if I new it would give good results. Thank you.