When the glass is rolled down almost to the bottom, is the most accesible on unscrewing the 2 screws that hold the glass onto the track.
Bob, 4 SpeedFish and I did both of mine last week.
I used to do them myself along time ago. I was a little rusty this time. Was like re-learning spanish again I took in H.S. It really helps if you have somebody there as a second set of eyes.