Thanks for the reply, Beaky.
Clip one end of the wire to the bracket that the sound board is mounted to and with the other end ground each of the following pins one at a time, you should get a different sound from each pin. 10J3 pins 2, 3, 4, 5, 7.
No sounds from pins 2 and 3 when I did this test, the other pins produced a sound when tested.
By the way, I got the button-tops off the old diagnostic switches (brute force did the trick).
