Help: Hooking up tachometer

[Safebet]

I have a 1985 Yamaha, Model 150 ETLK, mounted on a Ebbtide 179 Dyna Trak.

I am attempting to install missing tachometer.

I have the following wires:
2 green wires tied together, which I think goes to the "signal" post.
1 black wire which, I'm sure is ground, goes to "Grnd" post.
1 purple wire, which I believe goes to "Ignition" post.
1 blue wire which I think is lighting, and
1 gray wire, which I don't know where it goes.

Some sources say the gray wire goes to signal. If that's true, where do the double green wires go? Do both the gray and green wires go to signal.

Please help me out.

Thanks

Jim
Diana, Texas

 

[Ru4rusty2]

Re: Help: Hooking up tachometer

Hers a link to yamaha wire colors

http://www.maxrules.com/fixyamahawiring.html