Installing glass

[msaintg]

I have a 1947, three window truck. I purchased all new glass and rubber for it. Now I am wondering how to put it in. The rear window rubber is one straight piece. I assume the 'seam' or 'joint' where they meet should be at the bottom-center, but how do I figure out what length to cut the rubber to? Do I need to glue the ends together? How do I get the glass in without breaking it? That question goes for the two windshield pieces too. On the windsield, the gasket is a little small, so it comes away from the frame at the pillars. Do I start in the center and work out, or start at the pillars and work to the center?
My original plan was to have a glass installer just do this, but I have called three of them and they won't touch it. Excuses like.... they can't warrenty it and they don't know if it is safety glass or not.... blah, blah, blah.

thanks,
MIke