Depending on how fussy you are for accuracy you might want to consider "J" or "U" nuts like PICTURED HERE. You can get these at ACE hardware, I believe.

I can't remember but I think those might have originally been "cage nuts" like pictured HERE. but I don't recall seeing then at the hardware store.

Anyway, there are a couple options to consider.

Woody
Your Brother in Bolthood

My 1951 half-ton 'Ol Red

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