The Detroit News plans to move the following stories for clients of the New York Times News Service for editions of Saturday, March 20, 2010. For questions, contact: News desk: 313.222.2533 Sports desk: 313.222.2260 Features desk: 313.222.2480 Business desk: 313.222.2738 BUSINESS ('f') GM (Washington) -- GM supports mandatory 'black boxes' in vehicles. It's new head of gov't relations also thinks mandatory brake-shift override systems that would allow the brakes to stop a car with an open throttle are 'reasonable.' By David Shepardson. Developing. TOYOTA (Washington) -- Documents released by a House committee show Toyota's efforts in 2007 to head off a larger NHTSA investigation into its floor mat problems as the company strategized a 'game plan' to beat back a tougher requirement. By David Shepardson. Developing 