I had the same problem with my lens being scratched up shortly after I bought it. I paid $35 at a local dealer to get a new one and tried to be more careful with this one. However, I can still see scratches when the sun hits it just right.
I took it out over the weekend and used Mequiar's clear plastic cleaner (#17) and then the clear plastic polish (#10). It made a big difference, but when the sun hits it just right, I can still see the scratches.
I have thought about covering the lenses with a clear film, such as contact paper or laminate or somethig similar. I bought 3 different rolls at 3 different places. Two of the rolls were supposed to be clear laminate, but were not clear enough to see through. It looked like I was looking through a fogged up window. The third had this adhesive that is probably stronger than the welds on my 4Runner. Once it was placed, there was no way to cleanly remove it and trying to get all the air bubbles out was a total pain. I cut my losses and removed it and then had to goo-gone the adhesive. So,in the end, I spent over $20 to protect a $35 lens and it's still unprotected.
If there are any suggestions on which film would be sufficient, please pass it on. A guy that has tried 3 different products would certainly try a forth....
Tom