When I think "snapped a spark plug", this is what I picture. Not hard to do if you aren't using the right tool.
But I think this isn't uncommon (but I'd think you've gotta work a lot harder to do it).
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Steve
'08 Boxster RS60 Spyder #0099/1960
- never named a car before, but this is Charlotte.
'88 targa
SOLD 2004 - gone but not forgotten