Steering Box Universal Coupling Sizes

I see most sellers of the A body manual boxes for 63 to 72 list the input spline shaft as 5/8 dia (.625) which is identical to the power steering box size that I pulled from the 65 Dart.

The slant six forum people think the rebuilder possiblily shipped a C body box instead of an a body and improperly labeled it.

I've checked a 65 manual pitman arm and it slides on properly

I was hoping to solve the issue by finding a coupler with a .723 dia spline that would fit the box & avoid the hassle with the steering rebuilder that is acting like my Dart was modified.........

What size coupler is used on 73 & up boxes?