I would also use this after doing the wetsanding routine, and I would start with 500, 800, 1000, 1500, and end with 2000. Then a good compounding (Menzerna), polishing with Plast-X or similar product, and then give an IPA wipe down to be sure you polished out all scratches.
Use this to seal, great new product that leaves your headlights basically factory sealed so they don't yellow again:
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