Where are the catalytic converters located?

Hello, it looks like the Catalytic converter is part of the exhaust manifold on this vehicle, I will post a diagram showing the entire setup,
Are you getting codes (Check engine light) for the Catalytic Converter? P0420?
Converter failures are usually due to cylinder misfires, where excessive unburned fuel is entering the converter and causing it to overheat. They don't usually fail on an engine that is not having fuel system issues.

There is a Technical Service Bulletin I have been seeing quite a few times already that GM sent out and it has to do with the Ground wires for the Ignition Coils not being properly crimped to the terminal ring that bolts to the engine block, the information on this TSB is below (diagrams 3-6). And these bad ground locations can cause resistance in the ignition coil ground circuit, which in turn limits current flow. It looks like this would cause cylinder misfires that are not noticeable or detected by the engine computer, causing premature Catalytic Converter failure.
There is also an additional 3-way Catalytic converter on some models above the lower engine cover (diagrams 7-9).

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms