Need help finding technical information on a 01 GT ECU

I posted earlier trying to figure out what to do next with my 01 GT. I ended up getting a K & N Filtercharger because I could run out to my local auto parts store and install it in 5 minutes. I'm thinking next I'll get an Accufab 75mm TB with Accufab plenum.

However, I'm still thinking about the 4.10 gears. I think I could install the gears myself, but I really don't want to pay to have someone recalibrate. I don't really want to buy a Steeda recalibration box for $110 or buy a new ECU. I want to try to build my own recalibration box (<$50 for materials + a lot of time). I need to know for sure what ECU is in a stock 2001 GT (I think it's the EEC-IV, but I want to be sure) and then I need a technical document on the ECU with a pin diagram and an outline of the specifications for receiving data (i.e., format, sampling rate, parameters, etc.) so I can find a good microcontroller for the job and program it well. Anyone have this information laying around by any chance? Thanks.

I'm not worried about making the calibration box at all if I can find the information I need...just takes a little computer engineering work and that's what I do. Sounds like the installation can be a pain if you haven't done it before. I'm probably more mechanically knowledgable than the average human being but not as knowledgeable as most of you and I haven't done it before. I do have a neighbor who works on cars all day long, I might ask him to see if he's swapped ring and pinions before. Otherwise, my Ford service center is quoting me $450 for install and calibration (not including the cost of the gears)...there's no way I'll be paying that. There's a couple other places I could check around town but it doesn't look good.