Ford Headlight Cataracts... There is, of course, a uTube... Basically it involves wet sanding till the film is removed, working up (toward finer) in grit numbers to somewhere around 2000, maybe it was 3000. Final sanding is done parallel to the ground to eliminate swirls and vertical lines. Then spray the surface with Krylon's clear paint in their product line that's meant for plastic. Econoline would be easier than many because you can simply pull the lamp out to work on it. Harder, though, because up to 2007 they still had bumps to set an aiming device onto. Newer lamps don't so there's a flat surface to sand down.