ive no time to read the whole thread but heres my tupence, If wanting to keep the original loom intact and use the crank sensor, edis4 and the injection loom (to the plug) then use megasquirt, because as far as i know its th eonly programmable management that can be used with edis. You will only require breaking into two of the edis wires, PIP and SAW, and as you say make up a plug for your injector/temps sensors. i would have a seperate wire for the throttle pot to save butchering the injection loom. Then the rev counter and everything else will work with no other wiring or modifications, and if you leave the original ecu in place this could be used if the system ecer developed a problem (i did this on my first MS car)