If your willing to wait till this fall, i've got a A-body 8 3/4 in my dart now that i'll be selling.
(changing to a Dana S60) in the fall. The 8 3/4 is fairly new, has a 4.89 case 3.91 gears, detroit locker and Moser big bolt axles , no issues no noises,can hear and drive if you want. Thanks