I disagree, I think the front windshield is taller on a 4 door car. The rear window is shorter on a 4 door car. I say this cuz I tried to use the stainless windshield trim from a 4 door car and it is different than a 2 door car.
I just measured my 63 2 dr coupe. Front measures 18" flange to flange with the windshield removed, rear is 20" flange to flange. My 63 4 dr with winshield and trim looks like about 20 1/4". Da**, I thought I could use it!
I just happened to have the molding off of the windshield on my 69 2 dr car. The windshield is 20.75 inches top to bottom measured in the middle of the glass. I also just happend to have a rear window for a 68-74 2 dr. car sitting in the garage and it is 24.5 inches tall.