If you have the standard Nardi horn button and trim ring, the ring just pops off ewith a little prying, bringing the horn button with it. Disconnect the wire to the button and set aside. You'll then see two small bolts that hold the wheel to the hub. Just get the correct size wrench or socket and have at it. The whole thing take less than a minute. If you have the Porsche horn button and a 6-bolt trim ring, those you an allen wrench. Just as easy.
No need to remove the hub to refinish the wheel.