Vent window glass loose

[Jethro]

When my drivers side vent window is open the glass slips a little. Before the vent window can be closed I have to squeeze the glass back into the metal frame a 1/4 inch or so. I'd like to use the vent but I'm worried that it might fall clear out and break.
What holds the glass in? Glue?
If so, what kind of glue?
I'm clueless and glueless.

[James]

Here is one location that have what you need. Item #9.

https://www.lmctruck.com/1960-66-chevy-gmc/vent-window/cbe-1960-66-vent-window

There are other company that sell this.

[AZKen]

Item 9 are the weather seals that surround the vent window when closed. Your glass is held into the metal frame with "Glass Setting Tape". You need to take out the whole vent window assembly to a carpeted bench and replace the tape. There is no glue, RTV or adhesive involved. It is a press fit retention. There are several thicknesses of tape. I'm guessing you need the 3/64 (.045) thick. Not sure. The tape is about $10. Some measurements will be necessary. Post again if you will be doing this fix. Otherwise you can buy the whole assembly for $300.

[Jethro]

Thanks AZKen. That's what I was trying to figure out.
I will be attempting the repair. Might wait until spring if the whole assembly needs to be removed.