The best thing to get a good change is to do just like the above 'How-To' says. Its a little messier but you'll get a lot more fluid out than the 'Flush n Fill' method.
Redcon,
The engine must be running for the pump in the tranny to be running. So no, you can't just remove the line and drain the fluid.
White,
If you can afford it Mobil 1, IMO, is very good for ATF. I certainly wouldn't go to a Ford dealer for the flush though, you'll probably end up with other problems just from Ford touching your car.
Numerous local shops should have flushing machines that will do a very good job of removing most of the old fluid. I think I was quoted $90 a couple years ago and I think that included the ATF.
I did the flushing method listed above and got a lot of the dark dirty fluid out. Like it says, the biggest problem is getting the drain tubing onto the tranny cooler line.
