Preheat the oven to 350°F.
Cook the jumbo shells in salted boiling water according to the package instructions. When finished, remove to a bowl of ice water to stop the cooking process. Drain and set aside.
In a small bowl, combine the ricotta cheese, mozzarella cheese, Parmesan cheese, Romano cheese, and salt. Using a spoon, fill the shells with the cheese mixture.
Spread the marinara sauce out on the bottom of a 13x9 baking dish. Nestle the stuffed shells into the marinara and top them with the alfredo sauce. Cover the dish with aluminum foil and bake for 30 minutes, until the marinara sauce is bubbling and the shells are warmed through.
Remove the foil and sprinkle the bread crumbs over the shells. Bake, uncovered, for an additional 10 minutes, until the bread crumbs and toasted.
Sprinkle the chopped parsley over the baked shells and serve immediately.