Yeah, not sure how they rusted that quickly. Like I said, I for sure pulled them last summer. I think water must be dripping through the sun deck and collecting there. Anyway, ordered a square tap in extractor. Threads I don't think are too corroded in there, other 3 came out without too much drama. The plug just rusted through . I always grease the threads before install. Hoping that's the actual cause of the miss. Rebuilt carb didn't help (looked clean on disassembly), all electrical connections clean, distributor cap looked a bit worn...