I bought a rear (post cat) NGK o2 Sensor and attempted to install it yesterday but was not able to locate it on the car. I do not have access to a lift so that could be part of the problem. I was hoping to install it myself but I have a feeling a shop is going to have to do this. Does anyone know were the rear 02 is located? I found the front o2 sensor on top of the exhaust down pipe.