I forgot the main cat has the sensor behind it. That bung will need to be plugged or closed. Or you can swap your cat out. And not that I think about it, you'll need to swap your front pre-cat as well. There is no bung for the downstream sensor.
Y-pipe swap for one with a bung.
Front pre-cat swap for one with a bung.
Main cat can either be swapped or plug the bung hole.(snicker)
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