I tinted windows for about 5 years and we tried pretty much everything under the sun to get dot matrices to look good (sanding, a special gel, painting, cutting out the tint and installing a black vinyl strip on the inside of the window), none of which worked that well, besides the vinyl strip.
So, if you have already removed the tint and you want to get rid of the residue:
- Get some #0000 steel wool and some foaming glass cleaner
- Spray the glass cleaner on the residue and start rubbing with the steel wool
If you have a safe way to heat the window (tough this time of year):
- Spray foaming glass cleaner over all the residue
- Cut down a garbage bag to fit the strip of window where the residue resides
- stick the bag against the window and let the window get heated up to where its fairly hot to the touch (time varies on source of heat)
- Remove the bag and use the steel wool to remove the residue (the steel wool will get gummed up, so you will need to use different sections of your piece or swap out if it gets too gummed up). The point of the heat is to soften the residue.
Good luck.
-Kody-