Add macaroni to large pan with sufficient water to cover (approximately 4 cups). Add salt and bring to boil until tender (approximately 25 -30 minutes). Meanwhile, beat eggs and sugar together, then add vanilla and nutmeg. Mix well and set aside. In a separate medium sauce pan, heat evaporated milk plus 1 cup of water and butter to almost a boiling point. Remove from heat and add to sugar mixture. Drain cooked macaroni. Add macaroni and raisins to the milk mixture and stir well. (This mixture will have quite a bit of liquid, but this will form a nice custard textured pudding once baked.)
Grease a large baking dish with butter or margarine, add the macaroni mixture and sprinkle with additional nutmeg. Bake at 350° F for 1 hour or until golden brown. (Pudding should be firm enough to cut, but moist and not dry).