Oh I see what you are talking about. You aren't suppose to use the center caps with a 4x4. I thought mine looked terrible, and I didn't want to chance taking a hole saw to a expensive center cap, besides I don't think just cutting a hole in the center cap is going to look much better. Here is what I did and it has worked awesome!! Mount the wheels without center caps on. On my center caps they inserted from behind and had three or four little flanges that would keep the cap from passing all the way through. I cut these off and smoothed the edges. Then I took 1/2" strips of good duct tape and started wrapping the bottom edge, but a couple layers on and insert it from the outside pushing it in towards the hub, if it is too loose put another layer or two. You want a good snug fit. I have the ESOF system and keep it working properly so I have never had to use the manual lock outs, if I ever need to, all I have to do is grab the center cap and give it a wiggle or two and it pulls right off. The guys at the tire shop thought it looked pretty slick. This has worked for me so I thought I would pass it along.
NCH