I will come back and edit this later. But I read an article that a fellow with a 89 or 90 B2 wrote about how close the 89-90 RBV's were to the 1st generation Explorers. I can tell you this, side by side there is very little difference.
these links will help you in the future, the first is plug and play: http://www.broncoii-ranger.com/forum...hp?p=9135#9135
The second is Tech Info from that site: http://www.broncoii-ranger.com/forum...017975b60ebeac
This is the Tech Library at The Ranger Station, also useful for the old RBV's: http://www.therangerstation.com/tech_library/index.php
As people are getting away from the older RBV's to get newer stuff, it is important to watch for places you can post and find answers to the problems that arise in the older stuff.
I am rejuvenating an 86 B2 by swapping it over to everything from a 92 Explorer, (wiring, ECU, front and rear axles, manual trans, exhaust, and what ever else that goes with it. When completed, it will be a 1st generation Explorer with a 86 B2 body) I got a dash from a 90 B2 and the interior from an 89 for it. The heater and air from the 92 are in with the controls from the 90 matching perfectly.
I will find the article and post a link on this reply.