is it a switch for a after market or maybe a stock alrm, or car start switch?? when i had my door poppers installed there was a switch like that, not in the same place, they said they used it for setting everything up....
it should mount to the backside of the key switch there is a small hole and 2 studs that it will line up with then it uses 2 pushnuts to stay on have no idea what its for