2003 OZ Rally/general exhaust question
 

So I bought my 03 OZ Rally off some inexperienced guy who neglected and riced it up, I'm currently in the process of scraping off the rice and correcting the maintenance, so far it's turning out to be a good little car. But one thing he did was cut off the exhaust below the manifold right after the first flange and welded on a duster pipe for whatever reason. So i'm piecing back the exhaust, and I see the original exhaust had the O2 sensor before the second cat underneath the car... I have some high flow cats laying around, but they have their O2 sensor bungs going INTO the cat, would that be a code problem? Could I use that instead of forking out 100 to buy another bungless cat and put the O2 sensor in the pipe before it to avoid engine codes?

Thank Odin for anybody who can answer these questions for me lol, can't find info on it anywhere

I'm not sure if it would cause a CEL utilizing the bung in the center of the high flow cat. I would recommend drilling out a new hole before the 2nd cat and welding in a new bung. That would avoid the whole code or CEL thing.

Yeah but my whole thing was I didn't want to spent money on a factory cat, or have to do any extra work to plug my high flow cat and drill a hole before it if I didn't have to.

Hopefully somebody will chime in with a dependable answer and save me a headache lol