Can be done commercially with a water cooled 4 inch disc polisher, using 20,000 to 50,000 grade tin oxide (white), or Cerium oxide (brick red). Both oxides have a Mohs hardness of around 8.5; windscreen glass is around Mohs 7.0.
Gem facetors (I happen to be a gem cutter), use these oxides for polishing the facets on cut stones, so I am familiar with the polishing powders that are used , and the grades used. I have cut and polished about 80 faceted gemstones.
There are specialists out there, who make a living out of polishing the wiper score marks from automotive windscreens.
I have successfully removed wiper score marks from the windscreen of my 6.9, using hand rubbing, but it is an awfully slow and relatively messy process. An electric 4 inch polisher is OK for this process, but it must be water cooled, or the windscreen will crack due to localized overheating. I used 20,000 grade cerium oxide; 1/2 kilo bought from Naxos Chemicals.