Let me know if you want a 90 (Ranger) 4wd Automatic trans PCM (
engine computer). I have one,
free for you. You can reimburse me the cost of shipping after you receive it. I have no use for it and it sounds like you will need it for your transmission swap.
The 90 4wd Ranger it came out of did NOT have EGR on its 2.9.
So, this PCM supports a 2.9 automatic, no EGR.
You will need to send me a Private Message.
Include your mailing address and I will ship it out this week.
Other than that, you will need a small transmission harness for the automatic, which will allow you to connect the neutral safety switch, reverse lights, etc. You don't HAVE to change the pedals, but most automatics have a wider brake pedal, as you know. You will obviously need an A4LD, a flex plate and remove that pilot bearing.
Good luck finding an A4LD, unless you are planning to have it rebuilt before installing it. There is a lot of A4LD info over here:
http://www.explorerforum.com/forums/showthread.php?t=146956