I have done one window it was only the small window in a crx. I used this
http://www.reidmfg.com/ sort of scary you have to get it under the glass and pull cutting the old seal and sealer. Got a new seal and use 3m window sealer it didn't leak (it is not as bad of and angle as a front windshield). I do not think I would ever want to do that again and definitely not tackle a big window (maybe if it was not my money).

Thy have a power tool (looks crazy)
http://www.equalizer.com/07/

I do not like the fact you cant even mess up once. But if you mess up you are out 50 bucks or you are in the same scenario you are in now.

Found this http://www.wikihow.com/Replace-Your-...ile-Windshield said use urethane trust this over me.