A Ford source at PRI let it slip that a live axle version og the 2015 S550 Mustang will debut next year at PRI.
Part of Ford Racings new program the S550 will be offered body in white, which is essentially a stripped down shell ready to be built up bonkers. The 9" rear is expected to cater to this program.
Its not likely the conversion will be simple, so don't expect to swap in a new live rear to handle all the mad powerz of a cold air intake and borla pipes in your driveway with box ends and a few sockets. Its likely going to require a full rear subframe swap.
But if you're looking to run 2000 ponies and meaty slicks this is for you