1970 duster door glass is loose

I have the same problem on drivers side. I took it apart last fall and there is a "tube" that runs vertical. At the top of that tube was a bolt with a LoT of slop, as if there was a bushing something missing. It seemed to be the source of my problem. I can't find so much as a picture of the assembly online. Anybody know anything about it? This may be Travism's problem too.

You mean like a window track guide roller?