So, lets look at why this might work, and some theory behind it. Put on your thinking caps kids, it's time for school!
The 5R is pretty much just an updated version of the A4ld. Same case, same bell housing, same length, same mother-in-law. So the actual bolting it up and having it installed in a first gen is the easy part.
The similarities, however, pretty much stop there. It is HOW the transmission is controlled that is the bugger part. See, the A4ld is hydralically shifted except for the 3-4 shift and the TCC shift solonoids, which are grounded out by the EEC-IV computer. Three wires, that's it. The 5R is completely electronically controlled, having 6 shift solonoids internally (4 for the actual shifts, one for the TCC, and one for the EPC).
I won't go into why I am doing this swap, as we all have been there. Loosing overdrive, burning clutches, ect. So how can the 5R work in a first gen? Well, on the surface it wont. The EEC-IV has no ability to shift the 5R and never will. BUT..the EEC-V pcm can, which I'll get to in a bit..
Now lets compare the 4.0 OHV motor in a first gen between that of a 4.0 SOHC out of, lets say, a 97. When Ford engineers began designing the SOHC motor, they didnt start from a clean sheet of expensive white paper. They tore the OHV down to bare essentials, and began designing. While the blocks are in no way interchangable, they are similar is casting. So having said that, ford engineers pretty much used off the shelf components in the motor. And when i say off the shelf, i mean sensors as well. Both motors use pretty much the same values for sensors between each other. This is why its possible to run a SOHC motor in a first gen using the EEC-IV computer and harness. The SOHC does have one additional sensor, the Cam position sensor. But from my research, i believe this is irrelevant. Even though 93-94 OHV recieved the same sensor. But I digress..
Ok, so what does this all mean? Well in order to shift the 5R, the EEC-V uses the readings from engine sensor data to determine things like line pressure, what speed to shift at, when to downshift, ect ect. So, using arbitrary mathamatical properties we can deduce that..
EEC-
IV Sensor Value X = EEC-
V Sensor Value X
thus
EEC-
V Sensor Value X ~
5R Shfting
Ergo
EEC-
IV Sensor Value X ~
5R Shfting
Ok, so now that we know that an EEC-V PCM can read and interpret EEC-IV sensor data, we have a game plan to make this transmission work. But how? Well, there's the beauty and curse of this swap..
The First gen will be running two computers
Yep, I said it. My plan is this, and this is the technical part: The EEC-V PCM will be 'piggy-backed' off of the EEC-IV harness inside the cab. It will only recieve inputs from the engine (MAF, TPS, Tach, HO2S, Crank sensor, and a couple others) and will only be able to output to the 5R through an actual 5R harness. The EEC-V will have NO motor outputs connected. It will simply be ran in parallel with the harness and, being fed motor sensor data, then it will, in theory, shift the transmission accordingly. Will it have a lot of MILS? You bet your overdrive it will. BUT...and here's where I am stuck out now for this swap...I need to be able to feed the EEC-V enough data without it putting the 5R into the infamous 'limp mode'. If I can do that, this thing is golden.
So now that i gave fried your brain with techincal mumbo-jumbo, wanna see some pictures? Here, I'll save yea the grief
The first thing I started thinking about it is 'how am I going to wire this up?' Well, in all honestly, I hate splicing wires IN the truck. Limited room, limited slack, ect. So I decided to add on top of this completely stupid swap, I wanted to make it 'Plug-n-play' and completely reversible. SO I bought this:
What you are looking at is actually a Rotunda Monitor Adapter Harness, part number 007-00081 for EEC-IV harness. It's actually a ford tool designed to extend the connectors for the EEC-IV for use with breakout boxes and what not, so the tech isnt crunched over in a floor board with the test equipment. $50 bucks on ebay. Then I bought all this for $40 bucks off a guy parting out a 98 on craigslist:
These are assorted male/female connectors, am EEC-V PCM harness, some factory relay boxes and then of course, the 5R tranny harness. Now its just a simple matter of wiring everything together and running the harness in the truck. Again, 99% plug-n-play like this. I like that idea
Oh, but then I also need a computer! Well, again, CL saves the day and I get this for $50 dollars:
This PCM is perfect: Out of a 97, SOHC automatic with four wheel drive. Again, PERFECT!! SO, where am I at in this swap? Well, I am still in the planning stages and research, but all I lack now to make this all work is an actual 5R transmission...but, crossing my fingers, I will know by next saturday (3-5-11) if I can get one. Once I get it, and a free weekend, I'll wire all this up, and install it in the truck (Blue Bandit) and we'll see what happens..
SO there you go. A completely insane and Russell-is-making-this-harder-than-he-should project. I welcome all thoughts, concerns, questions, angry mobs with pitchforks, et al. But please, be gentle...my ego is very very fragile
:....Yea, not really
Following along here and maybe be able to throw in my .09 cent worth here 
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