The First American Corp. and the Greenlining Institute are partners in a five-year program that uses guaranteed-cost mortgage packages to bring homeownership to low-income and minority homebuyers. The program also makes alternative credit-scoring products available to borrowers with less-than-perfect credit. It will be offered first to Californians early next year and be expanded nationwide, cutting closing costs by as much as 25 percent. The Greenlining Institute, a housing and inner-city economic development advocacy