A magazine assignment to imagine a forgotten luxury nameplate reborn somehow became a fully functional one-off, built on a genuine Shelby Cobra chassis and dressed in copper and brass. Commissioned by a metals trade association rather than an automaker, the Mercer-Cobra combined retro coachbuilt styling with real Shelby performance underneath. Decades later, it sold for $660,000 at a Monterey auction. How does a concept car built to promote copper end up among the most valuable one-offs in Shelby history?