Long story short, I damaged my Cat during some engine misfire issues I was having. Misfire is taken care of but now I have P0430 error code and I can hear some rattling going on. I am told P0430 is Bank 2 and that either the O2 Sensor needs to be changed or the CAT itself.

I'm pretty positive fuel got down into the exhaust system and ignited during my engine misfire and the rattling indicates the CAT itself is damaged.

QUESTION: Is there a separate error code that may display if the O2 sensor is damaged? Does both the CAT and the O2 sensor need to be replaced based on the problem I described above?

2ND QUESTION: If CAT needs to be replaced, is it a good idea to just get some high flow cats instead? Looks like kinetix is the recommended ones. Is this a relatively simple DIY I can do in my garage with the car lifted up on jackstands? (Slightly uncomfortable under the car I know...)

THIRD QUESTION: I live in MD near DC. The only shop I know of is AAM Competition which is now based in Annapolis. I called them but apparently they are closed this weekend (usually they are open). I'm stuck at work until 5 or so but does anyone know where I can get some CATS in the MD/DC/VA area so I can take care of it this weekend?