Picked up the car last year. Not sure what is going on with the quarter windows. It looks like it was rough rubber coating over the top. Everything I’ve read was sand, primer, sand, primer, seal, paint.
You’re lucky enough to have a Notch because they reproduce the windows for your car with the “mustang” script on the glass if your able and willing to drop 700 bucks. Big coin but saves the trouble of trying to refinish them depending on your skill level plus you get new glass as well. Just another option to think about.
PS: I love those old school key scratch guards! Very nostalgic!
yeah, the rubber breaking down is common. You'll need to decide if your windows are salvagable or if you'll need to source a different set of donor windows in better shape to start with. From what i can see, that's an awful lot of material you'll need to add in.