EDIT: Apparently
I'm not the only one. I'll go to home depot and buy a bolt. One guy used a bolt with an allen wrench head.
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OK, so my very first attempt to do anything on the Cayman has left it undriveable.
. I was just trying to add a battery tender adapter.
Removing the nut (which was completely loose to start) resulted in a lot of resistance. Putting it back on there was even more. But in the spirit of
I fucking want this down now goddamit I just kept turning.
Then I heard a pop and the bolt now spins freely inside the terminal clamp.