For 70-71, the link from the motor to the driver's side pivot was part #2822293 and crank arm part number 2822289, for 72-74 you would be looking for the link from the motor to the driver's side pivot with part number 3431102 (that's the one in my photos) and crank arm part number 3431518 on both Cuda and Challenger models.
The crank arm is the one I believe from your photos is a 2 SPEED crank arm. If that crank arm is not correct, because the bends and angles are different as you can see from my photo of the 2822289 crank I posted vs a 2 speed crank arm which is almost straight, you won't get the proper travel from wiper motor to windshield and that will cause, binding in some cases, wierd park positions, etc.