Most stolen cats are cut out with a sawzall.
I don’t care how good you think your welding skills are, reinstalling a cat that was removed with a sawzall will leave telltale welds.
The thief cuts several inches ahead of the converter, cuts the O2 sensor and the hanger, the takes the whole tailpipe including muffler.
Smog check doesn’t jack up the car or look for welds. They use a mirror and flashlight to look for the OEM markings on the casing of the converter itself.
I watched them smog check my Prius, which by the way had the new OEM catalytic converter spliced in from exactly where the sawzall had cut out the original. The mechanic dressed the end using a pipe cutter, then used a sleeve.
30 seconds and all trace of sawzall use is gone. Thanks for playing!
