Make sauce: In hot oil in 5-quart Dutch oven, saute onion and garlic 5 minutes. Mix in rest of sauce ingredients and 1-1/2 cups water, mashing tomatoes with fork. Bring to boiling, and reduce heat. Simmer mixture, covered and stirring occasionally, 1 hour.
Make Manicotti: In medium bowl, combine 6 eggs, the flour, 1/4 teaspoon salt, and 1-1/2 cups water; with electric mixer, beat just until smooth. Let stand 1/2 hour or longer. Slowly heat an 8-inch skillet. Pour in 3 tablespoons batter, rotating the skillet quickly to spread batter evenly over bottom.
Cook over medium heat until top is dry but bottom is not brown. Turn out on a wire rack to cool. Continue cooking until all of the batter is used. As the manicotti cool, stack them with waxed paper between them.
Preheat oven to 350 degrees. Make Filling: In large bowl, combine ricotta, mozzarella, 1/3 cup parmesan, the eggs, salt, pepper, and parsley; beat with wooden spoon to blend well. Spread about 1/4 cup filling down the center of each manicotti, and roll up.
Spoon 1-1/2 cups sauce into each of two 12-by-8-by-2-inch baking dishes. Place eight rolled manicotti seam side down, in single layer; top with five more. Cover with 1 cup sauce; sprinkle with Parmesan. Bake, uncovered, 1/2 hour, or until bubbly.
To Freeze: Line baking dish with large piece of foil; assemble as directed. Fold foil over to seal, and freeze in dish. When frozen, remove dish.
To serve: Unwrap; place in baking dish, and let stand 1 hour to thaw. Bake, uncovered, 1 hour in 350 degree oven.
*If not using a skillet with a non-stick surface, brush skillet lightly with butter for each manicotti.