Preheat broiler
In a small bowl add margarine and garlic powder, microwave for 7 seconds to soften. Mix with a fork until fully combined. Spread evenly onto 4 bread pieces. Place bread margarine side up in a baking dish. Place bread in broiler to toast.
In a medium mixing bowl combine beef and sausage, then form into 2" meatballs. Cook meatballs in a large pan until done. 5-8 minutes.
Place bread in broiler until browned, 2-3 minutes. Then turn oven down to 400F
In a medium mixing bowl combine peppers, olives, onions and spaghetti sauce.
When the meatballs are finished cut each one in half. Spread 1/3 of the cheese over the bread, then spread the meatball halves evenly across the bread. Cover with the sauce, then add the remaining cheese. Bake for 20 minutes, or until cheese is fully melted.