Rust - Limited Center Caps - Remove/Replace?

I was out washing my 2011 Limited this weekend and noticed a tiny amount of RUST forming along the perimeter of the center cap on my wheels. I also noticed a bit of a rusty stain on the alloy wheels themselves.


Not my wheels, but similar issue.

These caps are simply chrome plated pieces, correct? Or maybe the rust/stain is coming from behind (hubs/rotors)?

How to remove these caps? Not really room to inset a screwdriver in the gap. How about safely removing the rusty stain without affecting the wheel finish?

Ideas?

Thanks!

Note: The finish on my 2000 and 2004 JGC alloy wheels totally failed and flaked over time - I surely want to avoid a similar situation on my 2011!