Building on thewishman's response, why not go all out and have the silver bands span both the cap and the body of the pen, (on both sides), add a "headlight" at each end of the "grill" (some clear acrylic) and then do the finials on each end to look like the tires...?
Oh, and use acrylic instead of wood. If this is a commission, you could even color match it to the requestor's vehicle, either using commerically-available acrylic if possible or a custom-cast..