We occasionally do a few for the local guys rebuilding stuff. We have a small machine with a 4 foot rotary table and are using round steel shot. Rims need to be degreased cause the shot will stick in the grease and the rim won't clean properly. I can put 4 car rims on the table at the same time and with 2 to 4 times turning the rims over it takes about 40 minutes or so to clean all 4. Rust and paint are usually pretty well all gone down to bare metal. They need primer fairly soon or they will rust again fast. Unfortunately I'm much too far from you to be of any direct assistance.
Meltedmetal