I want to install an aircraft tachometer (it's a nice one and it was free and I'm a pilot) on my 06 sporty. Can anyone tell me what lead to use for the "signal" wire? Is it the LGN/V wire listed as Databus/Datalink? It's a three wire tach.....battery power, ground and signal. The first two are easy, just not absolutely sure about the third. Thanks!