Well finally a couple weeks ago, my window decided not to roll down. The lifter channel rusted to bits and ripped off the glass and bent into pieces, leaving the window wedged at an angle partially open. Luckily, I was able to unjam the glass and carefully lower it down to open the tailgate. This is what I found attached to the lifter arms:
After some thinking, I went to Home Depot and bought some 3/4" angle and some 1" flat stock, mocked it up on the glass, and tacked it all into position. Then I took it off the glass, and started welding:
Unfortunately, in my excitement and haste, I welded it too fast and caused it to get hot and warp a little. Luckily however, I was able to bend it back into shape and it became less warped as it cooled. Then I welded the old tracks/slots on, and the guide bits:
The final steps were to prime it, glue the glass in using Goop glue, and then paint it before assembly. It slid right in and fit perfectly:
Hopefully the glass doesn't mind being glued directly into the rigid steel lifter channel, without the rubber strip it was seated on in the original channel.
This is how I fasten the window in, a large washer and E-clip. The E-clips have stayed put for a few years so far.
Of course, while I was doing this repair, the tailgate latch handle which had bent decided to finally break, so I welded that back together and then reinforced it:
That whole pocket rusted out so I just cut out the remnants and rolled over the cut edges. To seal up the rust and make it look less terrible I painted it with some rubberized paint, which seems to work really well actually. I think I will use this stuff to paint the rest of the interior side of the tailgate, it's not as thick and tough as bedliner, but it's better than scratched paint and rust.:
