Hello all, on my right door, both window guides have fallen off the window glass and were found in the bottom of the door. On each, there's two grooves. There's one groove for the window glass, with little plastic holders, 2 on the rear guide, 1 on the front, and I've purchased the proper 3 new ones from M-B. The other groove on each guide rides on a metal track. Is that groove lined with anything? My rear guide has a bit of cloth with a rubber like finish, nearly gone. The front guide has nothing in the grove, so it was metal to metal contact. In the photo in this thread, it looks like the groove has something in it, what is supposed to be there? Thanks, Ron