I've studied the Haynes manual's wiring diagrams for the AC system, and it seems to be possible to re-wire it so that you can add a seperate switch to control the air conditioner.
This would be great, because I hate the "you don't REALLY want to have the air conditioned air directed anywhere you want, do you?" attitude behind Ford's climate control in the Contour/Mystique.
I plan to take the whole dash apart when I install a new head unit (Jensen MP3510. Plays MP3 discs!) and see if the wires coming out of the connectors actually match the ones described in the Haynes manual. If they do, then I'm going to give it the ol' "Trial and Blown Fuses" test. That is, unless someone in the Forums knows specifically that it doesn't work!
Hope I don't set my car on fire.