Just a word of warning using B&M's AOD shift arm adapter, the part that goes into the transmission is not hardened like the factory ones and where the nut goes on the inside on it is very thin walled and they tend to break where the threads are, tighten this minimally and use locktite on it or use a factory Mustang arm and flip it 180^ so it's pointing in the correct direction, you will still need B&M's cable bracket to attach to the tranny or make your own.
Good luck, Francois.