I've been putting this off as long as possible, but I'm at the point where I need to get the windows mounted. So today I cut out and trimmed to size the Right and Left rear Cabin windows. I used the Air Grinder w/the cut-off blades that Van's sends with the kit, they worked well. I went through a LOT of sandpaper and time before realizing that I could used the flat side of the cut-off wheel as a grinder. This worked much better and faster, just had to be careful, and not ding anything and not take too much off at a time. This stuff throws off a lot of grit, I'll cut out the windows for the doors tomorrow, and then think about cleaning up the shop.
Right cabin window trimmed to scribe line using air grinder and cut-off wheel