Power Steering Box Replacement

[noreastfish]

I just bought a rebuilt power steering box for my 70 Challenger.  I'm sure exactly what I need to do for the installation.  Do you somehow need to find the center of the spline that attaches to the pitman arm? I'm confused about how to line up the shaft to the pitman Arm. This is a factory power steering car.

[1 Wild R/T]

Pitman arm will only go on four ways, 90 degrees apart.. The correct orientation will be pretty obvious...

Steering coupler will only go on one way there is a single missing spline, if you look at the coupler that slides onto the steering shaft there is a notch that lines up with the missing spline.... See the photo below