Electric wiper motor measurement

I'm swapping to a different wiper motor on my Hemi/Javelin and can't find my old motor to get a critical measurement from it. I need to center to center distance of the stroke arm on the back of the motor. The dodge motor I'm using has a slightly longer arm as far as I can tell and it's causing my wiper transmission to bind. I need to shorten the arm but only want to cut and weld it once. The wiper motor is a 72 or possibly a 74 unit from a javelin. I might be using the 74 transmission arms since one set I had was broken and they were different between the 2 years.

I modified the Dodge arm and adjusted it for the proper park location and it all seems to be working fine now. My new motor is mounted inside the car and is not visable under the hood. This allowed me to use the leftover wiper motor mounting plate as a center mount for my under hood bracing.