I think on the LHS the only option was to use a stud (24-5205) as the presence of the snail cam on the inside of the lug prevents any protrusion of a bolt or overly long stud(5/16 max). On the RHS for some reason the 15-480 bolt was used but imho another stud was the better idea (as per post 1940?) as it's quite fiddly getting the bolt through the stud eyes and then through the lug. The 'sandwich' on both sides is only the three stays ie. around 3/8".
The KM24 and KM23 rear wheel 'drop-out' castings appear identical with the exception that the M23 version usually includes a sidecar mounting lug. The 531 seat stays and chain stays are really a separate thing but maybe I'm missing the point.
The next time I make some 5/16 studs I'll make some shorter 24-5207's
I have one on my bike and it is too long.
When making things like this you have to act in good faith, when so many versions are mentioned.
