A plan for light rail transit in the Twin Cities is begining to take shape. The LRT corridor management committee met this morning to agree on a budget--446 million dollars, and a route--from downtown Minneapolis to the Mall of America. There will be 15 stops in all instead of the original 18. To stay within the budget, the committee scaled back the number of stations and size of the trains. State Transportation commissioner Elwyn Tinklenberg says the proposed changes will save an estimated 50 to 70 million dollars.