I painted my rallye wheels with Dupli-Color "Hyper Silver" over their self etching primer. For the caps I used VHT's paint. I can't remember the name though. You should be fine, just be sure they are prepped well. I blasted mine, cleaned them and then did light coats.
Here are some pics. The wheel is just sitting on top of the tire.
View attachment 1715154718
View attachment 1715154719