As Dave said, I wouldn't worry about the ECU right now. You need to figure out the wiring first. Honestly, the best bet right now is to rip out the old and put in a "new" (as in "known good") wiring harness. Might want to give stangmurdera a call for that (Miller Import on here).
MB
Captain Caveman
96 RS Turbo 11.414 @ 119.62 MSNS, Crower 2 NA cams, BW366, 10.5 comp, UDP, 60mm TB, W/A intercooler, 3.55 tranny 567.9whp 430tq 97 RS NA 13.188 @ 103.87 MSnS powered 12.5 comp, Crower 3's and 219.4whp with 175tq 98 RS DD 12.5 comp on stock ECU, LTH, Crower 2's, Koni, GC, Hypercoil, DG hats 99 OZ 5sp Stocker 15.856 @ 85.97 99 GS stocker auto 17.7@77mph!