There are separate part numbers listed for the lens, versus the entire assembly.

Part numbers;89721-24470 & 89721-24480 are for the lenses. Dealer net on them in 1999 was only $16.05 each, as opposed to $277 for an entire headlight. I would assume that the lenses are easy to change, as they only have down 1/10 of an hour for labor to change one. This is after it's extricated from the front of the truck.

My lights are also starting to "get crazy" on the top around the horns. This is my second set of lights, having had them changed out shortly before my warranty ran out a couple of years ago. I can only assume that this is the effect the AZ sun has on clear polycarbonate I would imagine that this problem will continue, until the whole lens becomes cloudy.