Over the years I have seen several adaptations.
The most clever was one that did 4 wheels at once. Chain driven with a wheel on each side.
Seems like having some kind of drive to spin the wheels makes the most sense with paint. After you paint the wheels keep turning and prevent runs. I would weld up something that would put lug nuts in each hole so you do not have paint problems. Find some way to turn the wheels at a reasonable speed. The final consideration is keeping the wheel far enough apart that the over spray will not get on the wheel you just did.
I think creativity and supplies on hand are what drive each persons design.
Maybe someone will chime in with a good RPM to spin at for best paint coverage.