Update
Most of the cab has now been painted. Still need to paint the door and the filler panel for below the rear window. Have Bondo applied to the door frame, just need to sand, prime, and paint it now.
This evening, I cut and installed the first piece of plexiglass. I did the rear window since it was a separate frame, easier to deal with for the first one. That rubber gasket is a bit of a pain to install, but really turns out well, glad I sprung for it. Stuck the weatherstripping on too, makes a nice seal against the frame. Didn't get any good pics taken during daylight, had to run out and get a couple in the dark tonight.
The cab's looking pretty good now that it's all painted black. Should have some time to work on it again tomorrow night, should try to get the door primed and maybe painted for sure, maybe install another window too. Maybe the windshield, another fairly square one, easier cutting that way...