Post count: 42

Chances are 2 pins are for the circuit and the other(s) are support. Test for continuity across all the points, with the switch depressed and open.

If you do this on the switch provided with the GPIO board, you will see the outer 2 are isolated from the inner 2. And the corresponding holes on the board are also isolated. (Sometimes can be ground, but I didn’t see that. )

So for mine, I used a NES reset switch, I picked up the middle two points.

I actually soldered a connector there for easy removal.