Shakes, sputters and strong gas odor while idling. Need EXACT sensor location. on 2000 Jaguar S-Type

After extensive research I can't determine where on my Jag location of the sensors are EXACTLY. [Codes: P0153 O2 Sensor Circuit Slow Response (Bank 2 Sensor 1) and P0156 O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)] Can someone tell me how I find these and would the smell of gas indicate Jag is running too rich?

Asked by for the 2000 Jaguar S-Type