It's called "dead steer". Your power steering pump is under a tremendous load when your turning the wheels at idle and that's the cause of the whining. This is a normal condition . Fords are way louder than most. I prefer to help the pump out by reving the motor up a little bit if I have to dead...
Not me, but don't dissmay. You'll find some sick freak to do it someday. I won't eat yours but you can have some of mine if you'd like I'll mail it to you.
Mechanic with many mustangs here.If your 86 is set up the same way my 87 is you need a "multifuntion switch" very common problem, it runs your signal lights, headlights (high and low beam) and windshield wipers. Its a bolt on part with no special tools needed (mabey a torx screwdriver)...