[Monster]

aumoore,

It's difficult to tell why your windshield cracked without see it first hand, Usual causes are stress, impact, overtightend (bottoming out) screws on the support brackets touching the glass edge will also cause cracks. As for a "plastic that will resist scratching, Lexan can be used however the big caution is that if you need to use your wipers the windshield (and wipers) should be clean to minimize risk of scratching. The lexan scratch resistane coating is actually pretty good and I would think that occasional use of wipers should not be an issue as long as there is not a significant build up of dirt on the windshield.

good luck,
Mike "monster'