1stI'd check
www.baumannengineering.com - he says pre-88 AOD's are not worth working because they have inferior rear geartrain lube and are probably shot, also wear out quicker. Don't know if you can swap in later model parts or not. 88 & up AOD's out of 5.0 Mustangs are best common AOD. I did mine, used Art Carr kit because of what's in it. Also recommend their 2-3 "zero leak" accumulator and A od servo. You need a shift kit with "cutback" elimination (eliminates the pressure drop for the 2-3 & 3-4 shifts), Baumann good. Lentech has great valve bodies - check their website
www.lentechautomatics.com. YOu need special bushing drivers esp to get at the rear case bushing (from inside), and special lip seal installers for the seals in the clutch drums - I made out of alum cans, but real bear! The AOD out of a couple years of late model pickups have all the good stuff, incl the wide ratio. they may be longer tailshafts, but that stuff can be swapped. Better is AOD/E with good quality stock rebuild, $400 electric control box. Same bottom line and building/upgrading a plain AOD but end up with better trans. by all means check Baumann's site.