350zvroomvrooom

Hey everyone,
I need some help here. I've been searching and can't find any info. If I did miss it, I apologize. The car isn't even mine. Just trying to help out a buddy. I guess his car failed smog. His check engine light is on. From what he told me, it's "Bank 2 Sensor 2". From reading about it, it seems like it's the back o2 sensor on the driver side. But the o2 sensor isn't the reason for his CEL and failed smog test. They all told him it's the catalytic converter. He just said there's four of them. I looked it up and found a picture of the cat, and it looks like, it's the "front cat, o2 sensor and the back cat". Is that correct or is there another cat way in the back? I tried looking under the car without a jack, but I couldn't really tell.

So with him, thinking it's the back cat on the driver side, he purchased the following universal carb compliant cat. It's usually close to 200, but got a deal on it for bout 34 bucks only. If is' the "cat, 02, cat" and the back cat is giving the code, would we just cut off the back part, weld it on and it should be good to go? We won't be doing it ourselves. We're planning on taking it to an exhaust/muffler guy to do it at his shop.

This is what I'm assuming the cat(2 of 4) look like, and there's none after the second one.

https://images-na.ssl-images-amazon....L._SL1500_.jpg

And this is what he purchased, thinking a mechanic could cut and weld on the new back portion of the cat.

https://images-na.ssl-images-amazon....L._SL1500_.jpg

I appreciate any help or input. Like I said, it's not my car. Just trying to help the dude out and save some money. Thank you in advance!