Modeled a ring bearing for the 4mm bearing balls on hand, with a 3:1 drive for the antenna rotator.  

It was surprisingly easy to model (read as, the code is messy).  I now know just enough to be dangerous..  :)  I'll post it once I know it is strong enough like it is..

The ring bearing will let me center the screw drive motor and still make it easy to rotate the entire mast, motor and all, for aiming the antenna.

Printed.  

Looks like the first try came out basically perfect.  That's good, cause this was a decent amount of my precious nylon filament.

This will support the screw drive motor in the center, and rotate the pole.  

The screw will be where the hose was in my previous attempt, and mate with a coupling nut to push up the mast.

The screw drive motor will couple to the screw via a coupling, which I haven't decided on yet.  Just drilling a hole a tapered hole in the rod would be perfect, then a nut turned onto it would tighten it up very nicely.  Drilling a perfectly centered hole in a 10ft piece of threaded rod could be hard though.  I may just use a coupling nut and a spacer.

So that takes care of mounting the lift motor, and rotating it.  Time to finalize my thoughts on the screw.