Prepare rice mix according to package directions.
In a medium saucepan, melt butter; Saute green pepper, celery and onion for about 5-10 minutes or until tender.
In a very large bowl, combine the cooked rice, cooked vegetable mixture, mushroom soup, cheddar cheese, Swiss cheese and pepper.
Stir in the cooked shrimp; spoon mixture into a 3-quart rectangle baking dish.
Bake, covered with foil, at 350° for about 40 minutes or until heated through.
Let stand 10 minutes before serving.
Please Note: Nutritional values listed may vary from final results depending on actual measurements and brands used to prepare the recipe.