Misfire under load in open loop

[Mighty190]

K jet 81 380SL has a terrible misfire when warm. I unplugged the O2 and temp sensors and it runs much better but still misses some. If I get on it in second and let it pull through the gear it may miss once or twice. Ignition system all seems newer and spark is strong. So I'm assuming I need a new O2 and plugs to fix this?

I read about using this procedure on the 190 to test issues I had with that but I never saw any change with this because that turned out to be cam timing related.