Yeah, I might be able to find out what all parts are needed, etc. Actually, and I don't want to get anyone's hopes up prematurely, as it's probably at least a year off or so, but my friend and his other
brother are currently working on a piggyback ECU that'll control injectors, ignition and all sorts of other cool stuff you can think of. They've already got the boards and cases and have successfully got the injector drivers working in basic form. They've also got one working on an RX-7 Turbo II right now as a fuel-cut controller, to allow it to run higher-than-stock boost pressures.
Right now, the ECU only drives low-impendance injectors, but they already know of the potentially big Miata market if they incorporated a piggyback fuel controller, AFM delete option (by way of a simulated circuit through a MAP sensor, TPS, etc.) or an AFM-to-MAF convert , wideband autotuning, O2 clamp, ignition control (or at least the ability to pull timing, a la Bipes), water injector control via RPM, injector duty cycle, pressure sensor, MAP sensor, etc. The architecture is pretty open-ended, so really the possibilities are endless...they'll entertain whatever ideas people have if the market's profitable.
We've got some fun times planned ahead