OK..gotta make a couple notes here based on my experience trying to replace the trans on my 86 B2. My original input shaft broke and 4x4 trannies are somewhat scarce around here (Portland OR). My first attempt was to buy one from a 2wd Ranger but found out the output shaft is a lot longer, and can't mount the t-case. So.. found an early TK5 with the external slave system and discovered they are NOT the same even tho they look identical from the outside. The input shaft is shorter on the early models (83-85?) and the fittings for the external slave hydraulic system are different, so you'd need to change that. Side note...the fittings for the internal slaves in the late Tk5s are different and in a different location than the internal slaves on the M50d, so make sure you get the right one of you swap it out. If you can get by with just changing the retainer plate, that would probably be easiest, and I believe they are interchangable between early and late models, but not between tk5 and M50d. If not, I have a recently rebuilt early (external slave style) tk5 that I can't use and would love to get some of my money back out of it and only have 2 useless trannies in my garage. I've heard of people putting the clutch disc on backwards although I have a hard time understanding why, they're usually labelled and it doesn't fit right when it's backwards, but I've never heard of the throw out bearing being installed backwards. That must have taken a fair amount of work by someone who has no idea of how a clutch works. I'd make him buy the replacement parts...