Must investigate that Gumption, sounds like good stuff
I tried RayRay's method years ago to remove deep scratches, fine emery first then used the old Repo car polish, worked well
For 240Z tail lights to make them like new, I used a loose (not stitched all the way out to outer edge) cloth buffing wheel on a bench grinder and a small amount of fine buffing rouge, very lightly buffing the tail light lenses, too heavy and the plastic burns, so practiced on an old broken one first....results were pretty spectacular
Pete