I wasn't thinking about a permanent install. More or less just something to mess with to see what it says. I can run all but 2 of the wires from the radio. I just need to run the speed sensor and dol wires.
It's doable with a 89-93 N/A 3.8 or 5.0 since the PCM uses the same data feed as the digital cluster(pin 34 DOL with EEC IV), 4.6 and SC PCMs don't have the pins active so you'll be getting 200 MPG lol. All of the other circuits are there.
The speed part is dead on accurate from when I tested mine, I imagine MPG is fairly accurate as well considering the fuel calculation's done through the PCM from injector duty cycle.
The Ranger likely shared the same hardware calibration with the aerostar which did have a digital dash option. You could get lucky, but the SC hardware is pretty unique to itself and is doubtful the DOL pin would be active.