need help identifying correct wire for A/F meter

[midlifecruzer]

I want to hook up an auto meter A/F gauge in my '02 GT at the PCM wiring harness inside the passenger side kick panel. I read to locate a gray wire with a lt. blue stripe in the 104 pin connector to hook into the right o2 sensor, or a red wire with a blue stripe in the 87 pin connector to hook into the left o2 sensor. Trouble is, there are 3 wiring harnesses in there. Does anyone know which is the correct harness and wire. Or does anyone know another way? And how to connect the meter to the ignition switch? Thanks.