ES 125 Help Id

[deacon Mark]

This guitar belong to the late archtop maker Bill Hollenbeck. His daughter called me today and found this guitar of his she did not realize he had. It is a Gibson Es 125 and he wrote a note on the case he added a stereo pickup circuit to the guitar. This to me makes sense with the extra toggle switch. I get some more pics but this is what I have so far. Not sure of year 50's?

[floatingpickup]

That thing on the upper bout looks like it could be a pot, rather than a toggle switch. Looks like there is an extra tuner on the headstock as well.
Keith