Cut a hole about 2 inches in diameter in top of each bun; scoop out the inside, leaving about a 1/4 inch wall.
Place on ungreased cookie sheet.
Brush insides of buns with 1/4 cup melted margarine; spoon 1 tablespoon shredded cheese into each.
Cook in 350° oven until buns are slightly crisp, 10 to 15 minutes.
Mix eggs, milk, salt and pepper with fork until uniform in color.
Heat 2 tablespoons margarine in 10-inch skillet just until hot enough to sizzle a drop of water.
Pour egg mixture into skillet.
As mixture begins to set at bottom and side, gently lift cooked portions with spatula so that thin uncooked portions can flow to bottom.
Avoid constant stirring.
Cook until eggs are thickened throughout but still moist.
Spoon eggs into warm buns.
Garnish with olives if desired.