[DZEE'S LX]

So I got my $15 electric fan from a junkyard V-6 Taurus.
I got the Hayden controller kit, plenty of 10 gauge wire, and an extra relay for the a/c circuit.
Now I'm playing with the fan using jumper cables for juice and I'm a little confused.

The fan has three wires: Black (gnd), and two other wires, one with a red stripe and one with a green stripe. They could be a little different in color but they look like that anyway... Actually both wires split into two smaller wires and went somewhere in the Taurus wiring harness.
So I'm thinking it is a two speed fan where the fan spins faster when using + current through both wires when the temp switch and a/c switch are both on.

Here's what happens with the black grounded and touching the other wires to positive as follows:
Green only: Fan high
Red only: Fan low
Green and add red: Fan speed slows
Red and add green: Fan increases but not as high as green only.

I just used the positive end of the jumper for both wires because I figure both my relays will be seing the same battery voltage

I just want to understand why the fan does this and how to hook up the wires correctly.
I've looked at the websites that detail the Lincoln fan install, but the Taurus fan, which I have heard is similar to the 94+ Mustang elect fans, seems to be different.

Would appreciate help from any of you electrical gurus.

Thanks,
Dan