Thx for this reply,

Yeah, I wondered about that.
Best I can tell the O2 sensors are all the same, just different lengths on the pigtails to the connector.
I did double check mine are in the "correct " left and right spots, but the error codes are for the rear sensors, after what would be the catalytic converter.

Now that I've driven the car a couple of weeks and logged some miles, the smell is gone.
Next step is to lower the fan turn on temp and turn off these 4 codes.