I just today finished installing the two windows in my 53 one ton, and I can tell you it is a chore! The vent assembly needs to come out all the way, which is a bit tricky, then the window can be slid off the track. After the new glass is in, slide the window back on the track, then with it all the way down maneuver the vent assembly back into place. You also will need to get the upper part of the window channel out of the way where it meets the vent assembly.
Remember that there is a bolt holding the very bottom of the vent assembly in place, you have to reach up inside the door through the lower access panel. Not much room, pretty much do it by feel. I used two extensions on my 3/8 drive ratchet to get to it.
As long as the vent assembly is out you can replace the front channel. I couldn't get rivets to work, so I just glued it in with 3M weather strip adhesive, then let the window lock it in place while it dried.
It is doable, but can get very frustrating. I learned the hard way to do anything else I could before I put the window back in. I replaced the outer rubber seal, put some white lithium grease in the window track, and sprayed silicone into the channels to make it easier to roll the windows up and down. Even then I ended up taking the first door I worked on apart three times to correct mistakes.
But it sure looks nice now!
Good Luck
Tim
I am currently digging back in to a 1953 3800 (one ton) with a nine foot bed. I've owned it since 1979, and drove it until 1982 (or so). My wife got me involved in restoring it back in 2002, got the body removed and the frame redone, then things came up. Now I am retired and starting again. If anyone is interested I have photos on Imagur (
https://timwhiteblues.imgur.com/ ). I live way back in the woods in the Ozarks on 40 acres at the end of a 2 1/2 mile private road.
Tim