I've been re-wiring our '47 Mercury and I installed one of those aftermarket turn signal switches. Hooked up a battery today and started testing things. The turn signals all work, and the emergency flashers work. The problem is the little indicator light on the unit itself is on all the time. Even when the key is off. Here's the wiring diagram that came with the unit: It says on there; "For internal indicator lamp, switch housing must be grounded by contact with metal steering column." Which it is. So how do I get that indicator light to go out?