Kav,
Have someone guide the glass as you remove it from the arm, it will need to be wound up to about half way, so you have enough room to slid it backwards. If you have a mirror stick it behind the base of the window and you'll see the point the rollers have to go to free the window.
Then drop the regulator, and pull it out the large hole at the bottom of the door. There's a couple of hidden bolts behind the door, the hold a bracket that needs to come out.
Problems with the window winding up, can be a number of things, hopefully your teeth are O.K.
My guess is it's the regulator spring. The mounting for the spring snaps after years of use, allowing the spring to be loose. It's designed to help you wind the window up, that last bit.
http://www.pelicanparts.com/catalog/...INTPNL_pg2.htm
As you can see there are a couple of different ends, so you need to have a good look at what you have, as they changed through the years. Take note of how the spring is mounted, and the direction it's wound, as if you reverse it, it won't work as intended.
Replace your felt channel. By the looks of the photo, you have the hard channel at the back ( metal in the felt )? You can get the same, but the soft channel is just as good.
As they say in the manuals, refitting it is the reverse, of what you just did. Except for two things;
1. The frame need to be done up in a specific order, as to follow the contor of the car, otherwise it will restrict the windows motion, and won't line up with the rear quarter window frame, or give you a descent seal, around the door ( not that it's that good in the first place) I can try and get a scan of the order that you do the frame up for you if that helps.
2. When you remove the regulator, you'll see at the point where the rail meets the lifting mechanisium, a big nut (soak it whilst you've got it out, so it's easy to undo) it allows the window to level, as it rises. After you refit every thing, you need to loosen it, and wind your window up and down, so it levels itself to the frame. Once your happy just do it up.
Long winded sooty, but I hope that it helps.