I'd suggest getting what I call a scotch wheel. You can find them at Lowes, Home Depot...also at auto paint supplier. Kinda in line with scotchbrite.
It will remove any rust the wheel can reach, down to bare metal, which is what you want on something like that.
Watched a gent, using a 12" wheel, completely strip paint, rust, and anything else in the way, a fiftyish model pick-up, down to shiny bare metal, in 3-4 hours.