Different P/Ns for 1986 2.3 and 1990 4.0

[croatankid]

I just learned that the rebuild kits for my so called new transmission uses a different rebuild kit than the a4ld I now have in my truck. It's probably just a different O ring or something minor but who knows. Now I wonder if I should rebuild the older a4ld or put the older one in and rebuild the newer a4ld and then swap them again.