Slick 60's

Tips on removing front and rear glass to replace seals 64 C/C
Necco-2

get yourself a Stanley knife with a sharp blade and cut the old rubber at about where you think the edge of the glass is!, cut it right around ( from the outside), and pull the rubber away!, you may have to pry it a bit but be careful!. don`t lay the screen down on it front, try and stand it up against something!, don`t ask!, just believe me!

I agree that cutting the seal is the best way to save your glass. There have been times when I've saved the seal by using srewdrivers to work the inner edge of the seal beyond the lip of the window frame. I start itn eh center and work around to both sides. Once it is tucked beyond the l;ip on the top and sides you can tilt them out from the top. It helps to have two people to apply more even pressure, but most times I've doen this by myself.

Removing the windshield with supple rubber that way is is do able.however the older variety is brittle. I just replaced one of mine and an exacto or box razor knife is a must. I ran mine along the inside flange on the front window. There is a ridge in the rubber that I followed. Two people is a must when removing glass for the first time, tilt out from the top and slowly break the seal tilting and lifting a little at a time.
There is a post in tips I just found, that will help replace the rubber. do not soap or grease the rubber when placing it on the glass only the outside rubber when placing it on the truck.
John