If you dont trust the 5r55e then look into a 5spd manual swap with a good clutch. You have two options behind the 4.0 and neither will be cheap.
Advance Adapters does or used to make an adapter to swap a GM 700r4 in which I hear is only slightly better than what you have.The other option is c4/c5 setup. The bellhousing needed is a 2.8 c5 and are very hard to find.You will not have OD anymore and I hear getting a converter to work with it is a PITA.
Also since both those autos wont interface with your trans wiring you would need to convert your truck to a manual trans ecm most likely.
1983 Ranger 5.0,9in,d44,37" Iroks
1988 Ranger 2.3t