I believe 73 is the year for the different pitman arm. Also the steering coupler on the steering shaft is a different size between power and manual where it slides on the box, if you didn't already know.
I can't confirm or deny that difference in these early steering gears ( my memory fails ).
The column shaft will need to be approx' 3 inches shorter. Many have simply defeated the sheer pins inside the column shaft to shorten it. While not proper, it works.
