There's a switch that turns the fog lights on and off completely, and the fog lights turn off when you turn on the high beams.
At worst you need to wire up another relay and maybe a switch (if you want one). At best Ford did what they did with non-power seat Mustangs... Wired them all the same way, just didn't install a power seat. So if you don't have power seats, but want them: call Stang parts, bolt it in, plug it in to the connector that's already there, and you're done.
Unfortantly, I think this is an "at worst" (which isn't all that bad at all) case. Of course you could do what the Pony God intended for the fog light holes: Vent the front brakes!
