Murphy's law of fasteners. No matter how many screws/bolts/nuts you have in your collection you never have the one you need right now. Off to Ace hardware!
Also, I hate that Can't Phillip. The fucker who invented the Phillip's head screw.
Finally found what I needed here:
Just ordered up a bunch to fill a few drawers, and will get more next month.
Apparently I’ll have to add grade 8 nuts and bolts.