By Mike Colias DETROIT (Reuters) -Ford and General Motors are racing to sign up car dealers for programs that would effectively extend the use of a $7,500 U.S. tax credit on leases of electric vehicles beyond the Tuesday expiration of the federal subsidy, according to dealers and documents. Each company in recent days has rolled out programs to their retailers under which the automaker's financing arm would initiate the purchase of EVs in dealers’ inventory by making down payments on them, according to d ...