Thanks guys....I realized after getting back under the car Sunday morning that I am going to have to break the bolts behind the catalytic converter free along with the nuts at the top of the precat. There just doesn't seem to be any other way to get the sensor out of the hole except to remove the exhaust portion blocking it in. I tried putting a little leverage on the pipe to get just a little room between the floorboard and pipe, but not nearly enough give. Next time I get the chance I'll drop the pipe, pull the sensor, have more room to unplug the connection. I'm sure to need to replace the two exhaust gasketsbefore putting the cat/precat section. Anybody know those part numbers?