Initial effort involved getting it as hot as MAP gas was capable of doing. A 6pt 7/8" O2 sensor tool proved a very sloppy fit and it started to round the corners of the sensor. I stopped and over a five day period I applied Kroil and used a flat nosed punch/hammer to strike the shoulders of the O2 sensor several times a day.

Today I cut off the top of the sensor enough that I could get a 22mm 6pt on it and then went back to the MAP gas until it was as hot as I could get it. Using a breaker bar the sensor broke off flush with the converter.



I thought about taking the header pipe loose and separating the cat pipe from the front muffler but the exhaust system is old enough that I am pretty sure I will not be able to get the front muffler off of the cat pipe without damage to one or both- but that may still be an option.

Any suggestions on how to proceed would be appreciated.

Thanks,
Randy