Tach Question

["Matt and Stacy Sopher" <sopher@domain.elided>]

Hi all,
I have a SunPro Minitach that I've had on my shelf for a few years now. Now
I'm finally going to put it in, but I have forgotten which wires go where!
There are four wires;
Red- power?
black- ground?
green- negative side of the coil?
white- hooked up for light?
Or do I have the green and white mixed up somewhere? I don't want to hook it
up and see if this is right, as I don't want to break it.
Thanks in advance,
Matt Sopher