Catalytic converter bad help diag which one?

I am a Ford technition but being at a Ford dealer I am limited in capicty for diaging non ford vehicles so I am looking for a little help if possible. I am geting a P0430 code on my 06 taco so one of the Converters on the left side is bad but following the pinpoint test in All Data makes no sense and I am having trouble figuring out if it is the converter that is part of the exhaust manifold or part of the Y pipe.

Any tips on how to go forward on this without taking it to the dealer?

 

P0430 could also be the oxygen sensor monitoring that converter. Easy test is to swap the O2's from side to side, clear the code and see if you get a P0420 now. If so, cats good, O2 bad.

An old backyard trick we used on my mustang was to get the car jacked up, start it up, and let it get nice and warm. Then we rolled underneath it, and sprayed each of the 4 cats with a water spray bottle and watched how the water evaporated/dried. There was a clear difference in the one that was bad. Granted that was 15 years ago, so not sure if it would still work on today'a catalytic convertors. Might be able to see a temp difference with a infrared thermometer instead of using the water trick.