They will push out from the inside.
Stiff after all these years, work around the gasket, inside, lifting and flexing. Do this a time or two before trying to push them out.
I'd start at the top, front corner and while lifting the gasket back, start pushing on the glass. Push and peel the gasket, maintaining force.
The first time you'll think this just isn't going to work, but once things start to loosen, it is really a piece of cake.
The second will be a lot easier than the first.
Larry
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