What I'm not clear about is the exact layout of the two bearings that make up the 'duplex' bearing.
It seems the outer (nearest the spider) bearing is a roller bearing that takes the axial loads between the driving outer shaft that is spinning the TR and the inner control rod.
Is the inner (furthest from the spider) bearing attached by its inner race to the control rod and allowed to move linearly within the driving shaft or is it also an interference fit with the driving shaft but allows the control rod to pass through its inner race and move linearly that way?