Need help with external shift light

[KENS89LX]

I have a VDO Top Eliminator tach that has a built in shift light, and I also have a shift light that came off a Sun tach. The shift light has two wires and the Tach only has one for a external shift light. Can anyone help me on which wires the two from the light goes too. I have 5 wires coming from the tach there is a green one., red, white, black and a yellow one. The yellow is for a external shift light but I wonder if it for VDO only?

 

[jerryD]

normally the wires goes like this:

green - tach signal. or negative side of coil
white - illumination
red - key on positive
black - ground

by the sound of it, you would hook the yellow to your shift light, and then the other wire on the light to ground.