1974 Duster water leak

I have a low mileage '74 Duster that has a water leak on the passenger front side. The plastic liner in the glove box fills with water when it rains and spills over onto the floor and thankfully the rubber floor collects and contains it. I eliminated the cowl opening and wiper pivot points as sources for the leak by taping all those openings. I think it is leaking through the windshield gasket.
Can I just silicone around the suspected area or do I need to replace the windshield gasket????
Any and all advice is greatly appreciated!