Denny's method works well for the "glued in" windshields, but if I remember right your Nova relies mostly on the rubber seal to hold it to the pinch weld. Now some of those have had sealer squirted in around the seal as a bandaid and might need the knife/wire.

Otherwise, forget about reusing the seal, it's about time for a new one anyway. I use a utility knife to cut away the inner flange of rubber. You can try pushing on the inside of the glass then, around the edges, with a "catcher" on the outside. Odds are it'll be stuck too well to do that. That's when you resort to sitting in the seat, rubber soled shoes, and push it out with your legs. Work out toward the edges where there's less flex. If you don't have any dings the glass shouldn't break.