I built a couple of 4" diameter leg cleaning tubes with screw in clean out caps for my friend Welby Bergum. The 4" tube will hold four legs at once plus give you room to put your hand in there to pull the legs out when done. If you use a 3" diameter tube you can only do two legs at once plus you'll need a bent up coat hanger or stiff wire to snag the legs to pull them out.
Because my buddy Welby buys/sells/trades so many machines we're always using the leg cleaning tube. On those nice hot summer days where the temperature is 80 degrees or hotter, we were doing complete sets of legs in only two hours.
Here's a tip, if the machine was from an operator's route and there's floor wax all over the legs, put some floor wax stripper on the legs first. Getting that wax off is important so the Evapo-Rust can do it's job. Once that floor wax is gone then put the legs in the Evapo-Rust.
If the leg levelers are rusted stuck in the leg, put the whole leg in the Evapo-Rust anyway. It will leech into the leveler threads and loosen it so you can remove it.