The bulk of the money (almost $6 billion) will go to Ford Motors Co. for factory upgrades that will allow the company to produce over a dozen green cars that will improve fuel efficiency by at least 25 percent. By next year this could mean a few new Ford battery electric vehicles on the market and by 2012 a plug-in hybrid (the same year Ford is set to begin repaying the loan). Nissan will also be using some of its $1.6 billion to retrofit one of its Tennessee plants to …