Paint. My rallye rims gloss black?

Yup.
I pealed the plasti-dip off before I took mine in for powdercoating. It sticks really well but comes off clean.
I would take wheels off the car but leave the tires mounted. That way you can remove the centers and lugs unless you want everything black.
No need to mask the tires the natural break where the tire and rim meet allows you to peal it of the tire but if you mask the tire about an inch out from the edge of the rim there will be a nice solid line making it easier to remove the overspray since the thinner it is the more there is a tendency for it to tear off in tiny bits...
Glossy Plasti-dip requires applying a "Glossifier" top coat.
Lots of YouTube videos of plasti-dipping wheels on or off the car.

Thanks!