etl,
I would say if you can get them to a sand/ media blaster then do so.  They will be able to remove all of the paint (and any rust) from the rims and give you a nice clean surface to paint.  For an even more durable coating you could have them powder coated.  It shouldn't be too expensive as I looked into having my wheels two toned and it was going to be $200-$300 per wheel to have the chrome stirpped off of them, prepped and two tone powder coated.
				
			 
			
		 
			
				
			
			
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