My second 1965 Dodge Dart.

The right side wiper blade did not work well. It only wipe on the ends, while in the middle the rubber on the blade is not even close to the windshield. I suspected it was too little pressure and tried to take the arms off. No luck with that, they sit like it was cast in one piece. But, I discovered that the metal tab on the blade that is used to loosen the blade when taking it off was resting on the blade itself on the wiper blade on the right side of the car. It was a little opening on the blade on the left side of the car. I bent both arms and the blade is now quite a bit from the tab. The arm has no problems pushing the blade fully towards the glass in it's entire length now.

The bottom picture shows the left side blade, with the tab almost resting on the blade itself. On the right side it was the same, except there the windshield is curved more so it became an opening between the rubber and the windshield.
The upper picture shows the arm bent a bit and much more opening between the tab and blade.