Oscar week got rolling Tuesday on a Par soundstage with GM’s Ten, the carmakers annual intermingling of fashion (worn by celebs), cars (from guess who) and a concert (Beck with band.)The concept is pretty simple: The celebs walk down the runway and the cars follow them. It’s all about the visuals. If one thing stands out, it’s how polished the autos are. Brazilian models don’t get waxed like this. The ambiance was set by Best productions, which had covered every surface in white and installed a sound system powerful enough to communicate with nuclear submarines via undersea vibrations. As for the cars, the new ones looked great, but the 1952 Buick Riviera convertible stole the show. A hybrid version of this could be the ride of the millennium.