You both make very good points on this ...
I think that my course of action is going to be to build the dio "conventionally" (as Hans put it) and if it doesn't fall into place the way I've got it in my head, it shouldn't take long to re-*REPORT ME!!* and build a box set-up for it. Besides, even when doing a shadow box, you've got to figure out how the figures are going to be set up first anyway.
The BIGGEST plus side that I see in putting it together in a box, is that I wouldn't have to drill out and hide all the wiring and FO inside the figures. I would just be able to run them along the backside IOT hide it from the viewer.
As stated before, one of my biggest things is just being able to "look" around the model/ dio to see all the angles. But yes, as Hans said, building it up conventionally, it will be a challenge for me to get the viewer to look FIRST through the "NVG" film ... and THEN, if they want to look around it they can ... but it's all about that first view.
Still on the road, there's not much that I can do besides type, read, and think about it. Once I get back to the house on Monday, I'm planning on starting up some mock-ups as the paint on my current figure is drying. Hopefully, with a couple of days off, I'll be able to make a little headway and post some pics of my findings. Maybe then I'll have a little more insight on the direction I should go.
Thanks again guys for all your help and "debate" on the matter. PLS keep your thoughts coming ... constructive critizism is the only thing that makes us better.