DODGE OXYGEN SENSOR

I Have The Truck Listed Above 1500. I Went From A 5.2 To A 5.9 Got An Ecm For The 5.9 Change The Throttle Position Sensor, Idle Control...

Where Is The Oxygen Sensor Located On My 1997 Dodge Grand Caravan, 3 Liter V6?

Obd11 Scanner Says P0138, 02 Sensor. How Hard To Change And Where Is It? Or Is This A False Reading That Could Be Something Else?