Well, I spoke with my guy, and here is the answer I received.
"Windscreens are made of different materials, if its made out of acrylic you can polish it. Heat from the polishing pad will melt the screen! You have to go slow with a fine wool pad (wool is cooler
cutter) and do repeat polishings rather and one long working. I use Meguairs 105 as its a non diminishing abrasive I know how to work with, it also can finish down if you know how.
On your planes I didn't go for perfect, had to leave some heavier scratches, but you can improve them.
If you have the ability give it a try, but error on the side of caution. Find an old acrylic fish tank and practice on it first"
I do know from watching him that his polisher has a trigger that he uses to adjust the speed, and he was going REAL slow when working on the windscreen.
Hope this helps.