If you don't already have them, get some isopropyl alcohol at a concentration of 91% or more, and a cheap electric toothbrush (Crest makes one that costs about 5 bucks). Drop the windshield into a shallow container filled with alcohol and give it a soak for about 30 minutes. After that, use the toothbrush and work over the alcohol container so you can keep dipping the part and toothbrush in the alcohol to keep everything nice and wet. Just be gentle and patient and you should be able to get that smoke paint off of there. You may have to follow up with a Novus polishing kit if the solvents in the paint have managed to attack the clear plastic.