Gte wiring plug

[gte-87]

Hi I am in middle of putting bike carbs on my gte I have ordered a new ignition set up the main wiring plug that comes out by front wripper motor have 4 wires

1.red which I guess is live
2.black whcih I guess is earth
3.green is this rev counter
4.blue and red I am unsure what that is for

Thanks dan