i believe the third wire is for batch fire since ur speed density ? also One lead to the injector goes to 12v, the other leads goes to the ECM which is a transistor switch that grounds this lead i believe !!! someone correct if wrong >>

man is correct. if you notice on one bank you will have all the same color wires 1-7
and on the other bank a different color yet all the same for 2-8. Batch fired means all injectors fire at the same time from bank to bank. So the firing order being 18436572 it will alternat banks based on that order. Get it? or did i over simplify it?

Ha ha u explained it perfect !!! Very well simplified

No I got it, it just threw me off cuz I didnt think it looked factory, but whatevs.