Prick Potatoes with fork to allow steam to escape. Bake potatoes in 425F oven until tender, about 1 hour. Cool slightly Cut each potatoe lengthwise into halves, scoop out insides, leaving a 3/8 inch shell. Spread inside of shells with margarine or butter, sprinkle with salt. Cut each potatoe into six pieces, sprinkle with cheese and bacon. Set oven control to broil or 550F. Broil potatoe pieces about 5 inches from heat until cheese is melted, about 2 minutes. Makes 48 appetizers.