(Soundbite of song, "See the USA in Your Chevrolet") Ms. DINAH SHORE (Singer): (Singing) See the USA in your Chevrolet. BLOCK: Under the GM name, there is also Buick, Pontiac, Cadillac and GMC. GM dropped its Oldsmobile brand five years ago and it's closing Saturn and trying to sell Saab and Hummer. NORRIS: Plus, GM owns a 10 percent share of the Italian carmaker, Fiat, the very same company that Chrysler is now trying to merge with. And speaking of Chrysler, its brands include Dodge…