Black Box

["ken hedges" <khedges@wkpower.com>]

I know I will be told by some "not to worry "  or "it will never work"  but
I would like to know if anyone has a schematic / parts list for the black
box located behind the center console in a 75B.

The box apparently takes a signal from the seat belt switch and supposed to
illuminate a lamp in the console.

There is also a integral buzzer that I believe comes on if the  door is
open when the ignition key is left in.

Does anyone have one that works, and are my assumptions right?