I had thought about something similar, but havent come up with a viable solution yet. I dont want to just put a sticker over the top as its never going to look like its suppose to be that way. I was hoping there were some "kits" out there or something where there were blank horn buttons, you add your decal to it, then snap a clear domed cap over it so it looked it it was factory. I have found blank Nardi buttons, but nothing like adding a graphic to it.