The shaft gets attached to the box which is a fixed object.
I usually put the column in and snug up the two nuts that go over the studs at the bottom rear of the dash.
I then attach the bottom plate and then slide it around until the steering shaft is centered inside the column. (end of the tube sticking thru the firewall)Check it for placement front to rear and then snug up the two bolts that go into the larger plate and finishing tightening the upper column mounts. There should also be one low on passenger side that uses a bolt and is not a stud with a nut.
Be sure to put the pin in the shaft coupler on the box and then just plug everything in.
I modified mine to be floor shift as it was an original column shift. That's why you don't see a column shift bracket at the end of the tube on mine.
In the pics of the refurbished column above you'll see a white disc that goes inside and is held in by the spring clip...That's all there is and it is a bushing for the column shift part not for the shaft part.