I've been rocking these for almost 4 years now, NA and now boosted. Keeps the CEL gone, and I pass emissions every year with my cat removed. You do this to the second o2 sensor.

The visual inspection is only for a cat, the tester most likely wouldn't even notice if the o2 was sticking out, nor is he checking for that. Even a resonator will pass as a cat to some guys. Lol. I just had mine done in august and the tester only plugged my car up and ran the OBDII scan and EVAP test and sent me on my way.

Spark plug anti fouler, or non fouler. Autozone and the likes carries them, made by a company called HELP! and for my o2 sensor thread, the part number 42002. You use two of these bad boys (one pack), drill and bore out one of them with a 1/2" bit, to make clearance for the o2 sensor. So you'll have o2 into drilled fouler, into non drilled fouler, into exhaust