Now that's a wrench! I thought about radial pins or dog point screws (like your bolts) but these nuts look dodgy tuna can metal. A round pin only makes tangent contact to the side of the notch & these notcches are so shallow ~1.5mm. I feel a slip & chowdered metal experience coming on LOL. My hub wrench looks more complicated than it is, basically turn on lathe & mill the middle stuff away. I'm sure there is a laser cut 4-tang wrench in a far away land for $10 & 2 months shipping, but I may get after this a bit sooner. We'll see.