best to take the wheels to a bike shop to get the bearings pulled first.
Sweats is right, also If you are capable of removing the wheels your self, then have a go at removing the spokes too,
First off as he said take your wheels to a shop that has the tool to remove the bearings, Sealed bearing are notoriously hard to remove after time has aged then in place. most times the removal process can damage the bearings, removal tool uses the bearing center to drive them out, but installation uses a press on the outer edge to get them home.
consider new bearings in your costing.
You should use a spoke wrench to remove spokes, as it has a wide bite on the nipple, (dont get excited yet) if the threads are rusted, which happens, it will be hard to remove, pre CRC, RP7, WD40, to make it easier. You can not do any harm by removing them your self. BUT marking them to go back in the original place is and idiotic concept.
I think my 07 bonnie has stainless on the back from the factory...
Anyway let the powder coater do the masking as they will have to sand blast all the bits first to help with adhesion of the coating.
Then find an experienced wheel builder to reassemble with your old spokes or new stainless ones.
If all that is too hard or expensive then as Sweats said before... Spray bomb them your self. I suggest you look for a EPOXY enamel. The drying time is like 6 plus hours.... Brake caliper paint, engine enamel, etc. you will need to hand sand the parts first, and you can leave the bearings in place.
Bonus with that is when you get a tire replaced and the guy scratches the rim, you can retouch yourself ( dont get excited)
Maybe look for some used wheels on the net to experiment with and have 2 sets. chrome and black.