I have a client that had a few vehicles wrapped, they complained that the window perf was coming up when they washed, so we changed the last job to trim back the window perf and then we applied a clear 1/4" border around the edge to keep the graphics from lifting up. They love it now I need to do the remainder of the windows. I am looking for a clean way to do this without scratching there windows with a blade. Does anyone recommend a tool or technique that I can accomplish this with? Thanks.