OK, I haven't heard from CitriStrip yet (it being Sunday and all), but I went to my shop and looked at what solvents I had. One that sounded promising (and it was) is called Xylol or sometimes Xylene. It can be found in the same area of many stores as paint thinner, odorless mineral spirits, and denatured alcohol.
The label says "Xylol (Xylene) is a 100% aromatic hydrocarbon with excellent solvency characteristics and a medium-fast evaporation rate. It is the recommended thinner and reducer for hard-to-thin oil base paints and coatings such as anti-rust paints, porch and deck enamels and most other synthetic enamels. Xylol may also be used as a solvent for rubber cement and other mastics, and is excellent for clean-up of equipment and paint brushes. Note: Xylol is a powerful solvent, it may be harmful to some plastics and synthetic materials. Always test and inconspicuous area before use."
I used a piece of paper towel soaked in Xylol to remove some Silver Fire that was sprayed on a piece of Sinstra (a board made of PVC) almost a year ago. After the Xylol was in contact with the paint for about 5 seconds the paint started to liquefy! It wiped up nice as you please.
I then removed some mix that consisted of Behr and Valspar enamel paints mixed together off a piece of primed hardboard. It took a few seconds longer for the paint to turn to a pasty liquid, but it also came off with no need of scraping, just rubbing with the soaked paper towel.
Neither the hardboard nor the Sinstra was harmed; although I wouldn't recommend letting the Xylol pool on either for a protracted time.
To test the Sinstra further, I did make a small pool of Xylol on the surface and just let it evaporate naturally. This took several minutes and the PVC did not seem to softened or harmed in any way.
If I were in your shoes Matt, I would use Xylol to remove the paint from your screen. Keep in mind that this would be an outside job due to the fumes. The job could probably be done with just a can of Xylol and a roll of paper towels, but something like a fine 3M scouring pad might aid in the paint removal without scratching the PVC. Protective gloves would be a must, as well as eye protection; and a breathing respirator might not be a bad idea as well.
BTW, Xylol smells a lot like lighter fluid (naphtha). I tried that as well, but it didn't work near as well (if at all) as the Xylol as a paint remover.
I couldn't find Xylol or Xylene at Lowe's website, and Home Depot only had Xylene in a one gallon can for almost $20. I guess your best bet is your local hardware store (Ace, TrueValue, etc.), it should also be available in quarts.
