Mike,
What I did when I got mine from American Muscle was as follows....
First off the center caps were just a HAIR smaller than the stock ones, so there was a bit of wiggle room, too much to not do anything about it. On the inside of each wheel, I put 2 beads of crazy glue between BUT ON the center caps and wheel on opposite sides so the center caps would be secured to the wheel. The center caps are perfectly centered in the wheel, and won't move.
From the front, you cannot tell AT ALL, and even from looking at the wheel from the inside you can't tell either. I take it you are going to be installing them down in FL?
Don't forget w/ American Muscle you get 5% off by using our promo code found in our promos forum.