I would not bother with wiring into the ECU. I just need a stand alone with meter or gauge and o2 sensor. And like you said, test, get it right and remove it. I would like to pass smog the first time.. That's one thing that sells me on the LCI header over the DT unit. Too many complaints about the required smog fixtures beat to help. I also read that the DT headers are now made in Mexico at the Petronix exhaust factory. I will call DT tomorrow and ask a bunch of questions.
