My headlights were particularly manky, the local autoparts store had nothing, so improvised...Step 1.
Clean surface of headlight with glass cleaner.Step 2.
Mask off bodywork around light.Step 3.
Using a lambswool rotary buffing pad and liberal amounts of cutting paste, (used in bodywork repair, similar to 3000 grit paper), to keep the surface cool, work the surface of the polycarbonate with the drill on a slow
speed else paste will go everywhere!.Step 4.
Clean off all the cutting paste, then using T-Cut and a cloth, work the surface until glass smoooooth.Step 5.
Polish with Wax.
The whole process took nearly 3 hours, but the result was worth it