We have purchased a house where the previous owner decided to sell "mid-renovation". One of the projects left unfinished for quite some time was the painting of virtually all the windows. He painted many of the windows and neglected to scrape them at all. Now there are thick strokes of paint on the glass panes and they have baked on over a long time. It took over an hour to remove the paint off of one window with a razor blade, and there are several dozen. Any advice on how to do it easier? Chemicals or other tricks?