I took a different approach. Like Carlos, I wasn't happy with the look but in a different way. I thought the skins with the fully covered center were for the front and the 2 with the hole in the center were for the rear. I also thought the castle nut sticking out looked hokey, so I used what I thought was for the fronts to the rear. For the fronts I found some aluminum fence post caps, widened the center holes and the result are in the pictures.
The 2 rear skins still have the center sticking out. I don't have Carlos' cutting skills. I liked keeping the front dust caps & rear castle nuts covered.