ok i have a 1970 monte carlo and some of the lead is starting to lift onthe upper corner of the windshield and i pried it off and it was like 1/4 inch thick i was wondering how i can remove the rest of it i was thinking heat but i do not want to warp my roof and what would be the best besides lead to fill it in i was thinking usc all-metal would work thanks for any help you can give

A hand held propane torch will melt it out. Dynaglass would be a good choice for filler.

to minimize warpage. get a wire brush( disposable one ) and wave the torch flame along the seam. ( NOT the roof) As you pass it back and forth along the seam line.. you will notice a color hue change to the lead.. then use the wire brush to remove the softening/melting lead.