Finally dragged it all back to the hangar, after wife expressed desire to use the kitchen table to eat again. (Extended by sprained back and unplanned days of down-time).
Finished switch panel by hand-cutting (drilling/filing) to install the Cessna-type Master/Alternator switch to the left of the removable switch panel. Then match drilled and added #6 nutplates (C/S screws) to the switch panel.
Finally positioned the panel for a test fit to double-check wire harnesses and functionality. Need to decide next on a label method, and thinking 'side-lit' engraved plastic insert held in-place by switch nuts.