I will also be shortening the windshield on my O7 but will be cutting it down. Friend of mine use to work on planes and can buff the scratched one back to pristine condition if cost is an issue or if you simply don't want to change shields yet for a few more years. may be a consideration. He uses a cut polish of some type (I could find out what), and a variable speed buffer. cleaned up the windscreen on a very old, very scratched up 78 wing for me couple of years ago. It is just a thought.
Wally
Spring seems a long way off