Blend sugar and oil; add eggs. Sift flour, baking soda, 1 tsp. salt, nutmeg, and cinnamon. Blend together and add carrots and raisins and/or nuts. Grease a 9x13 pan and dust with powdered sugar. Pour batter into pan. Bake at 325 degrees for 1 hour. Cool completely. For the frosting, blend 1/4 tsp. salt, butter, cream cheese, vanilla and powdered sugar. Frost cake.