Cook shrimp and cut in halves. Arrange 5 of the cooked noodles in the bottom of a 9 x 13-inch buttered baking dish. Cook onion in butter until tender; blend in cream cheese. Stir in ricotta, egg, basil, 1/2 teaspoon salt and 1/8 teaspoon pepper. Spread half of this mixture on top of the noodles in baking dish. Combine soup, milk and wine. Stir in shrimp and crab meat. Spread half of this mixture over cheese layer. Repeat layers. Sprinkle with Parmesan cheese. Bake, uncovered, at 350 degrees for 45 minutes. Top with American cheese and cook about 3 minutes more, until cheese is melted. Let casserole stand several minutes before cutting.