Wild Guess: You'll have plenty of leverage to spread-open the O2 sensor socket, and round-off the sensor flats. BT,DT.
That's when I bought the socket I linked-to.
A guy who works with my wife needed an O2 sensor changed on his Dodge Charger/5.7L Hemi. The shop he took it to told him they couldn't get it out, he should go somewhere else. "Somewhere else" was me.
24", 1/2" drive ratchet with a 3-foot cheater pipe on the end. Enough overlap so that the whole lever arm was just over four feet. Took BOTH OF US pushing on the cheater pipe. "SNAP"! Good thing we were braced, or we'd have fallen over. Sensor screwed right out after popping free. Mind you, I tried everything including a 3/4" impact wrench and got nowhere prior to the ratchet-and-cheater-pipe deal. An O2 sensor socket would have been useless.
I use plain ol' commercially-bought "copper" anti-seize. Best I can tell, that's what Champion supplied for aircraft use--but I've never bought the Champion brand. Permatex or Loctite copper anti-seize for me.
Lifetime supply:
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Or stop at any decent auto-parts store, they're likely to have something similar locally. Reduce torque on nuts/bolts/spark plugs that have had the threads lubricated with anti-seize. I use 80% of "clean and dry" torque spec as a rule-of-thumb.