If the threads are crossed on the one plug hole, you can use a spark plug thread chaser with a good coating of grease on the end so it holds onto the little chips of carbon & crud and keeps them out of the cylinder.

There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!