I chose to order the
Axle Exchange driveshaft sold by American Muscle. The primary reasons were it was
less expensive than all the rest ($648 after 6% discount), and shipping was free. It
often goes out of stock and American Muscle, so be patient. They'll eventually get
some more in.
Well, I gave it a shot, but didn't have the room under the car, nor a way to break
the front bolts loose (the back ones were much easier). So I pussed out and took the
car to a nearby Mustang-oriented performance shop, and they swapped it out in about
an hour. I have an appointment at the same shop for my gear swap.