I made some Lexan headlight covers and am going to tell how to do it. These will help FE for us with the older style "bucket" headlights, with a lower cost than replacement composite headlights.
You will first have to make a template of your surround. I used poster board and made the template by laying it over the surround and cutting to the outside edge of surround.
Once you have the template take to a plastic company in your area. A sign/graphics place is a good place to start, or glass shop's normally carry it also.
The lexan I used is roughly 1/16 inch thick you don't want any thicker or it will not bend to form.
You will need to heat the lexan with a heatgun (not a hair-dryer) to give it a bowl shape first.(This enables the lexan to curve away from headlight not suck in towards it) Do this by heating the front outside face in the center, while holding by one edge. You will see it deform into a bowl shape. Do this very slowly while moving heatgun in large circles. Do not sit in one area move fast, or it WILL warp the material. You don't need alot of curve only a little. Like a foam Dixie plate. Only takes a few seconds to accomplish this. The curve will go away when cool, but remains in the plastics "memory" so make sure you make the outside somehow like using a piece of masking tape.
Some more steps are explained in pictures.
Here are some pics enjoy.