Is there a way to prevent headlight oxidation BEFORE it happens?

[Dwatted Wabbit]

I've used Rain-X on our 2001 PT Cruiser since 2002. It's been mostly garage-kept, save for probably two years of apartment living. The lenses look very good today.

I bought stick-on covers from Weather Tech but have not applied them yet.

[UrbanAdventurer]

You just have to replace them at some point. wet sanding takes the original layer off and they usually yellow much faster after you do that.