Adding MIL light from LS PCM to factory gauges - 86 Monte Carlo SS

[paradigm]

On the 86 Monte Carlo SS, the factory gauge harness has pin #13 which is a yellow cable for the check engine light.

However, there are two yelllow wires on this pin. Which one of these should I tap with the LS PCM MIL wire so that I can accurately display the check engine light?

I cannot locate the factory OBD port anymore on the car, I believe the correct MIL yellow wire goes to that port.

Also do you guys supply the factory coolant temp and oil pressure gauges with the LS PCM outputs, or directly from the sender units?

Thanks