Having a few issues with my 2 door need advice Please

[white2Door]

So it all started (i think?) with my SES light coming on and off and it was throwing an o2 sensor code. Well i procrastinated on changing it and now my SES light is on at all times. Now the truck runs ok but has a loss of power and when im at a stop light it will start running really rough and it stinks. Also where my exhaust tips exit out back it turned the bumper and lower 1/4 pannel corner black from the exhaust. I know its due for a full tune up about now, but now im guessing it also needs both cats and o2 sensors? What do you guys think? Is there a place to get decently good cats for a good price? Thanks in advance for any help and advice.

 

[SunlitComet]

It sound like one or both off the O2 sensors have failed and if they fail completely you will get black and stinky and performance drags balls. The code will specify which one has failed and how. Fix that asap and maybe your cats will be fine. There are codes that will tell you if you need new cats. That is one purpose of the rear O2 sensors.