Wiring Hella 500's

[AZ DESERT RAT]

I was using this diagram as a guide, but I have a 3 prong switch and this one seems to be for a 2 prong? http://www.naxja.org/forum/showthread.php?t=90011&highlight=hella+wiring (it's the last post on the 1st page). Can someone maybe clarify on this?

 

[robsewter]

The third prong on the switch you dont see on the diagram is a ground for the switch.

 

[AZ DESERT RAT]

I figured....bought thought I would ask, thanks.