Interesting catch... I just rec'd a set of same bolts from Corvette Depot so had to go take a look. Likewise, mine do not have cotter pin holes however the nuts (not castellated) are a self locking type - distorted on one side. Easy to start, but when the bolt reaches the distortion, it will stretch the nut and lock in place. Guess this is supposed to take the place of castellated nuts/cotter pins. Anyone else familiar with this?