I have the same guitar:
They are not valuable but certainly rare. I have struggled to date them. For the supposed date of manufacture, they should have a metal nameplate instead of the painted logo as far as I know, so that doesn't add up....
It is a "stereo" guitar - the top three and bottom three strings are split to left and right outputs. The switch at the bottom changes it from stereo to mono output. The pickup switches allow you to do things like top three strings on neck pickup and bottom three strings on bridge pickup and so on.
