Big day - got the lights in and finished the support structure for the lower dome.
I used open/loose bulb sockets that I could screw down into the wood, and tapped them into a ight to medium duty indoor extension cord. Then I tapped in a large, chunky switch to mount at the rear of the base.
With the bulb sockets, I installed four - two facing up for the upper dome, and two facing out for the lower (could not face them down due to clearance issues. I installed four. If that is too many, I'll just leave one or two empty. Also, I can choose any bulb I want - incandescent, compact flourescent, variable wattage, etcetera.
In addition, I added the angled struts in the pics. These will help transfer any weight pressure applied to the outer rim down to the robust central supprot - the lead pipe.
Finally there are two added vertical struts fromt he inside of the south pole up to the underside of the cog wheel hub. This is in case I picked the whole rig up by placing my palms where "Antarctica" would be; the vertical struts will transfer energy away from the acrylic on up to the central support system, preventing damage to the acrylic at the bottom of the model.