No..No.. don't touch the original O2 sensors or wires, it will mess things up. Stock O2 sensors are what are called "Narrow Band" (higher frequency) which means they switch at very high rate up and down whenever each single plug fires, they feed the computer. AFR gauges are usually run of a "Wide Band' (lower frequency) O2 sensor that switches much more slowly and reads an average of all the plugs firing. You need to take it to an exhaust shop and get additional bung(s) welded into the exhaust for the additional WB sensor(s). Need one for each side so you can move it back a forth, when you want to test each bank.