If my measurements are correct the 6 lug rim is 8.5 inch lug spacing and a 5.5 inch hole. I have seen a number of International School busses with a six lug 22.5 tubeless rim. With the correct tire, OD should be about the same. I haven't had a change to try them on my '59 but if they fit I'll keep an eye out. Schools are always selling retired busses and surplus tires, some pretty cheap. Grigg's tire & wheel article in Tech Tips spells out the hazards of the types of wheels even if it doesn't cover 56--59 specifically.


Matt

"Brunhilde II" '59 Viking 60
To paraphrase Ben Franklin: "Big Bolts are proof that God loves us and wants us to be happy"