[Milsurplus] Courier 1M microphone connections

[antqradio at juno.com]

Does anyone have a copy of Sams CB-8 handy?
I've been scratching my head on this one.  There seems to be a lot of
signal plus DC 
switching going on using only three wires and a ground
I have a question or two on how to modify an old four pin mike to control
the above radio.
Yea, I know, more of a boatanchor question (1961 CB radio) but I stopped
subscribing to 
Boatanchors since so many are also subscribers to Milsurplus.
No, I'm not going to use it, it is a repair for a friend.
Regards,
Jim