You can gawk all you want at new-car reveal photos from any auto show in the world, but only with exclusive PopMech TV footage can you watch the all-new, Mustang-throwback Shelby Cobra GT 500 KR series from Ford do its strut—and listen to its mighty roar. Ford Motor's tech gurus gave Popular Mechanics the first chance at turning the keys on this show-stopping new king of the New York...