We can't think straight, our mind's a mess, we only see straight when we're being led...straight into this eBay auction for a partially-stripped 5/16-18 nut. According to the seller, "This nut has been in storage for some time and is as good a shape as the day that it was set aside, except for a bit of corrosion." We're so there. [Thanks to the Undead Mister Coonce for the tip.]
Partially Stripped 5/16-18 Nut fits Ford chevy Mopar [eBay]
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Deux Chelimo on eBay! [Internal]