I was going to say, can't you just grind down the bottom part of the castle nut giving you the clearance you'd need for getting the cotter pin through?

Don't know if it is an anal freak thing, but it is one of those little things that get overlooked and they are kind of obvious when wrong. I have extras from past cars but they are not impossible to duplicate. If you look at them the have just had a mill take a pass and remove three of the points. The repop is just not quite right. It may be a GM or Ford part that the depth is wrong on. I imagine if you had a supply of them and had them plated correctly they would be easy to sell. Not having them would be like say a perfect breast enhancement and someone left off the nipple.

Not to hijack the original posters thread, but what are these castle nuts worth anyway?
I have never thrown anything on the ground, and left it there, when picking suspension parts, off cars since they invented U Pull It wrecking yards, around here, back in the early 1980's.
I probably have a storage container with about 30 pounds of castle nuts in it, and probably handfull's of those original 3 tower ones.
Think i should start selling them, to all the guys that are anal freaks for original castle nuts?
I remember when NS1AAR got a handfull of them from me, as we have known one another, for decades.