The door panel and covers for the access port had long since been removed. I used this special tool for removing the door handle retaining clips.
blocks_image
blocks_image
blocks_image
blocks_image
I removed the screws that held the window in place, and also removed the channel that the window slides in. Note that the longer side of this channel is vertical.
Some time ago, I restored this channel by gluing a sheet of black canvas fabric around it. The window fuzzies, were gone, so I replaced them with a strip intended for a sliding patio door.