Updated 7/6/2018:
I notched and test fitted Table #5. It is too wide and must be cut to the proper width. Therefore, I have left it and Table #6 lying in place as spacers (not fastened down). See photos.
These tables are temporarily acting as spacers for the divider sections (1/4” masonite) that must be installed above them. In the photo you can see one of the 3 masonite divider sections leaning against the vertical 2x2”. I’m using carpenter shims to help place the divider sections. The photo shows all the pieces just before test-fitting. I’ve got to move the 2 track lights and notch the top right section of the masonite to clear the lighting track.
The debate I have been having with myself revolves around cutting openings for the hidden reversal tracks and entry/exit tracks for the Staging Area. I could try to cut the openings in the divider before I put it in place. Unfortunately, my ability to accurately place these openings is appallingly similar to my success picking winning lottery numbers or horses. In other words, it sucks. Therefore, I am going to install the dividers, lay down the sub-roadbed and track, move it around until I’m happy with the geometry, and then fasten it down. After that, I will know where the reversal track entries / exits and the Staging Area portals should go. A plunge type cutting tool like the Saw Max followed up by a saber saw should do the trick. This approach should work, especially if I pull away Table #5 to get another 5/8” of vertical clearance for the cutting tools.
Here's the first of three masonite panels that form the divider. It is partially installed.
Because of some inaccuracy on my part or the warping of this 2"x2", I don't have enough of the vertical support to anchor the adjoining masonite panel. The answer is to install another 2" x 2" next to this one.
That's it for now. 
George
