I have done wheels before, I built a 2x6 frame slightly larger than the wheel, then laid heavy plastic sheeting inside and filled it up only enough to cover the wheel. I took the axle, cones and bearings out of the wheel, then put a heavy layer of grease in the cups.

The wheels I used this for were from a Paramount. They had the original chrome plated spokes that were rusty. I only left it in long enough to clean the spokes, they were not in long enough to damage the aluminum parts. It worked quite well.

Just a note.....if the spokes on the wheels you are planning to soak are zinc plated, they will discolor and look horrible after OA.