Need help to mount these

So I was in a speed shop yesterday out of town from me and found some bullet style center caps I liked but I need ideas to mount them...and before any of the purest get upset, don't worry these are for my 56 Dodge p/u not my son's a body! Anyway I want to simply have a bullet cap by itself with 5 chrome lugs but the caps I bought don't have a lip to push through from behind but they do have a center strap with threaded hole I can't run a strap across the back because of the axle poking through....
.ideas I will post pictures.

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