Help with 1971 dodge dart steering

If you take the pitman arm off and turn the steering left and right to find the center and put the pitman arm back on, the steering would be centered. It would take the same amount of turns side to side.
Yes, the pitman arm is splined and so is the steering wheel for a reason.
Possibly, the problem could be that the steering box count wasn't the same turns side to side and the pitman arm was put on one turn of the box too much to one side.
To adjust the steering wheel so it's centered, you turn the adjuster sleeves on both sides where the outer tie rods are.
This is the only way to properly center the steering wheel.
And the alignment shop should know that as well as the steering box centering technique.
It's alignment 101 after all.........