MAKE CREPES: In medium bowl, combine flour, melted butter, eggs, egg yolks, and 1/2 cup milk: beat with rotary beater until smooth. Beat in remaining milk until mixture is well blended.
Refrigerate, covered, at least 30 minutes.
Meanwhile, make ORANGE BUTTER: In small bowl, with electric mixer at low speed, cream 3/4 cup sweet butter with 1/2 cup sugar until light and fluffy. Add 1/3 cup Grand Marnier and 1/4 cup orange peel; beat until well blended. Set aside.
MAKE ORANGE SAUCE: In large skillet, melt sweet butter. Stir in sugar, orange peel, and orange juice; cook over low heat, stirring occasionally, until peel is ranslucent--about 20 minutes. Add orange sections and 1/2 cup Grand Marnier. Keep warm.
TO COOK CREPES: Slowly heat 8-inch skillet until a drop of water sizzles and rolls off. For each crepe, brush skillet lightly with butter. Pour in about 2 tablespoons batter, rotating pan quickly, to spread batter completely over bottom of skillet.
Coook until lightly browned--about 30 seconds; turn, and brown other side. Turn out onto wire rack.
Spread each crepe with Orange Butter, dividing evenly. Fold each in half, then in half again. When all are folded, place in Orange Sauce in chafing dish or skillet; cook over low heat until heated through.
TO SERVE: Gently heat 3 tablespoons Grand Marnier in small saucepan just until vapor rises. Ignite with match, and pour over crepes. Serve flaming. Makes 6 to 8 servings.