I am running them on my 1946 3600. They are 15" 8 lug lock-ring type split rims. I've got 235/75R15 tires on them, and the radial makes it much nicer to drive.
Unless you know EXACTLY what you're doing, I'd take them to a farm implement store and have them mounted there -- or if you've got an industrial tire supplier nearby, they can do it for you too.
