Hi

Yes, my 89 has red/blue and red/green wiring on the wiring harness just as on the drawing.
I got quite a lenghty reply from a guy at the garage today about polarity in solenoids. If the solenoid has a iron core, polarity doesnt matter as the core always wants to return to "zero" in the coil. Its different if the core is magnetized. I think he knows his stuff, phd scientist guy buildning cars and stuff :)

regarding that they fire synchronously, how does the ECM know which bank is firing as the tbi lacks crankshaft position sensor?

BR
/Alex :)