Yes ChopTop, I primed them first. Before you do that though you have to wash them with wax and oil remover to remove the mold release that was sprayed in the molds when they were made. You will be able to get that at the same place that you buy the paint.
Realistically though Choptop, if you haven't done a lot of this and you really want it to look top notch, spend the time that is required to clean the flash out of the honeycombs. After your hands heal from that, then fill and sand out the imperfections in the outer ring.
The prep for this is where all the work and in turn, hours of labour charges are. You will have a better job in the end if you let the pros do the painting. The center grills were easy once the prep was done as was the base on the outer ring. The hard part is spraying the clear and getting it shiney, really shiney.
I did the outer ring myself and I wasn't happy with it. Yeah the colour was great but it wasn't as smooth and shiney as I would have liked. I ended up taking the rings to a pro and I'm glad I did. I just wish that I hadn't spent all the money on paint for those rings that I did.
The results speak for themselves though and I am anxious to get them installed.