I've had to support head units in a few cars. Namely GM's with the legendary microwave sized opening. BUT, I've never heard of any trouble with the FORD sized openings. I for one am very very impressed with the stability of my head unit. Never had a problem with it cause a skip.
BUT, if you are wanting to support it, you will have to do some nifty work with your hands. Fist take out the HU, then get in there and see what you can do to beef up the support. Worth a try I suppose. What kind of HU are you running?
Jason