I have an 04 Rubicon w/ 183k miles and I’ve been receiving this code P0423 code after short idle periods. Assume it’s either a cat and/or a sensor in bank two. Any suggestions? Should I go ahead and change out the entire cat system (all 3) or just change out the four sensors? No performance issues or any exhaust leaks that I can tell. Also, how difficult is the entire cat system to change? On a scale of 1-5 on technical abilities, I’m probably a three. No welding though. Thank you!