Yesterday, I replaced the catalytic converter as the 2 hole flange at the resonator end had rusted away, I had trouble with getting the rear O2 sensor removed to put into the new converter, I was disappointed with my HF sensor socket, it just spread open and rounded off the sensor , I ended up using my die grinder and a cut off wheel to cut away the threaded bung enough to be able to unscrew the sensor

You can see the cut marks here in the old pipe bung

Here is tge O2 sensor with a light coat of copper never seize ready to go into the new converter pipe.

 

Changed idler and pulley, serpentine belt and both vvt solenoids. Changed oil too!! Really wasn't bad to do.