I've done that, it really wasn't too difficult to do. I took pictures years back when I did it but I'm not sure where they are. Since I used a digital a/c unit I figured out what resistance the temp probe returned at a high and low temp and matched resistors to those and use a relay to switch between the resistors. So when I want the ac running I make it think the temp is 85 and when I want it off it thinks it is 65.
I have mine hooked to a manifold I built with PVC and solenoids for each of my brewhemoth fermenters.