Hello. Nathan mentioned a Euro tune or Euro 1 tune, which involves removing several items including all 4 O2 sensors and secondary air pump, mentioned in the linked video at about 3:54. I am looking for more information on that tune, documentation, procedure, etc.

Nathan, you have been a huge help to me. Just wanted to say thank you.

https://www.youtube.com/watch?v=2jVgzwtLjeY