1. In a skillet, cook sausage over medium heat, until pork is no longer pink; drain.
2. In a Dutch oven, cook pasta shells according to package directions; drain and rinse with cold water.
3. Using a pastry brush, coat sides and bottom of a 3-quart baking dish with oil.
4. Pour half of the marinara sauce into baking dish.
5. In a large bowl, combine eggs, ricotta cheese, 2-½ cups of mozzarella, ½ cup Parmesan cheese, Romano cheese, basil, pepper and prepared sausage.
6. Stuff shells with meat mixture; arrange in baking dish.
7. Pour remaining marinara sauce over shells.
8. Cover and bake at 350°F for 30 minutes.
9. Uncover; sprinkle with remaining mozzarella and Parmesan cheese.
10. Bake 5 minutes longer or until cheese is melted.
11. Sprinkle with parsley.