I am going to clear the lenses in my front bumper. Should I use lexan or plexi for them? Which will stand up best against snones and pitting? also can i glue either one to regular plastic without the glue reacting or something?

Plexiglass and Lexan are virtually the same thing. They're just different manufacturers. Both are better choices than acrylic which is more brittle, but both will show wear faster than the OEM lights.

Well what would be the best choice of material for longest resistance? I might consider using a glass plate with rubber gasket seal but I want to use something i can glue on if possible.

Lexan is significantly stronger then Plexi... Those lexan nalgene bottles are "bulletproof", and they're not joking.

I would definately chose lexan over plexi.

You really shouldn't use glass unless its specially made for an automotive application or something.

would lexan get pitted from crap ont he roads? and where can i get it? home depot? do i need special glue or something to make it stick to the plastic lens?