Ran my codes on the 2000 SS and it says all 4 of my o2 sensors are bad. I'm looking for the ac delco sensors and i'm trying to figure out what the part number are. The code reader say bank 1 and bank 2 sensor, and sensor1 and sensor 2 bad. Now i'm just guessing but bank 1 would be drivers side? And sensor 1 would be up stream? Anyone know the part numbers (ac delco) and which one is which. I've only been able to find AFS123 right hand pre converter, AFS98 left hand post converter, and AFS97 right hand pre converter again. Any help would be greatly appreciated.