The method of removing the channel from the glass that I have used is to clamp the glass to the top of the work bench with the channel hanging over the edge of the bench. Place a cloth of uniform thickness between the glass and the bench. Place 2x4 wood block on top of the glass with a cloth between the wood block and the glass. A towel works good as a piece of cloth with uniform thickness. I use a 7 inch 'C' clamp to clamp the glass to the bench. Needless to say, if the clap is over tightened the glass will crack. Then take a small block of wood about 3/4 inches thick and about 2 inches wide and about 6 inches long and tap the channel while holding the block against the channel and striking it with light blows with a hammer. The block of wood should laying flat on the glass when striking it with the hammer. I have used this method several times and have not broken any glass. As for removing the vent window frames from the glass, duct tape wood strips to the jaws of your vise. Paint stirring sticks cut to the length of the vise jaws work good for this. Clamp the glass in the vise and and hold a small block of wood against the end of the metal frame and strike the wood block with light blows from the hammer. As for putting the glass back in the channels, I fill the channel with black silicone and center the glass in the channel with tooth picks and let the silicone set up over night. After the silicone has cured, the excess can be removed with a razor blade. Using the silicone make a real clean and neat looking installation.
