After much searching and reading I've found a fair bit of info on this.looking at new large cap hei distributors I see which color wire goes to which pin on the 7 pin icm.my understanding of the pickup coil is that the rotation direction affects the output signal for triggering a spark event.it puts out a wave that is converted to square wave and the trigger should come from the later side just before it drops again.and having the p and n wires backwards would mean it gets the trigger signal from the beginning of the square wave rather than the end where it's desired.I hope I understand this correctly. My question is looking at a corvette large cap hei the icm pickup is wired the same as my cadillac 4.5 distributor but they rotate in opposite directions. Which has left me confused. Is it the ecm that configuration that decides which signal or at which part of the square wave is the trigger. I also found a diagram for megasquirt and it shows the pickup coil wired opposite of the factory wiring.so more confusion. So which way should my set up be wired.my distributor rotates ccw and is wired like factory.but my ecm came from a sbc that rotated cw.the symptom I've had since day one has felt like the timing just isn't right and no matter where it's adjusted or how well it runs it just feels like it has this miss to it.in checking plugs I don't have any that stand out looking different from each other.if anyone with knowledge of this can help that would be great.