I managed to hookup my MS1 using a V3.0 Board, with megasquirt and spark to my 1993 Tercel with a 12 valve 3E-E engine. I didn't change the wiring harness. The only thing I changed was the spark module. I took out the stock Toyota spark module and used a VW spark module (see MS Manual for proper bosch manual with smart dwell control). The engine runs like new after only a few hours of tuning using no wideband meter, narrow band meter or EGT gauge. Tuning done strictly by ear has the car running the same as it did before, minus the right timing curve for maximum horsepower.
Here is a video of the engine after 3 hours of tuning. It took about 3 hours to get the car started and then 3 hours of tuning, so 6 hours or more to get it to run this good. There is many hours left of course.
1984 Toyota Celica 22-R Turbo @ 6 PSI. 120 PSI fuel pressure. Hand made down pipe. Nissan Turbocharger.