Been there. Dun that! PIA ain't it!! Still to this day have not got the pass. side to quit being a beotch to "roll its own" w/out paging "The Incredible Hulk" <img src="/forums/images/graemlins/lol.gif" alt="" /> to work that out!
Actually, the track for the front of the moving glass needs "tweaking" to get the glass to quit "rocking" as it goes up and down, if that is correct Southern for it digging into the track at the edges of the glass track. Too loose. Bend the track at the mounting point in or out against the glass/away from to eliminate. Oh, and biggest help is to USE it (unlike what I DON'T Do)

LUCK!!! <img src="/forums/images/graemlins/smile.gif" alt="" />