another germ

[Pursuivant]

I think that the mystery word for switch 11 in the bottom panel is: "STW'SS"

which I take to be an abbreviation for Stewardess. It might make sense given that flight attendants were always female back then. The shape of the letter is sort of similar to the W in "Switch" from the placard at the top of the panel.

I'm not certain that I'm right, though.

Sadly, there's nothing in any of the pilots' manuals about using the intercomm system or the lights, and the C-47 electrics are very different (different switches for various phases of paratroop drop, formation and recognition lights), so no help there.