In a large zip-lock style plastic bag, combine garlic, limejuice, cumin, oregano, oil, salt and pepper. Add steak to the marinade, seal bag, removing as much air as possible, and turn to coat well. Marinate for at least 1 hour at room temperature, or overnight in the refrigerator, turning occasionally. Remove steak from marinade and drain well. Grill steak on a well-oiled rack set about 5-inches over glowing coals for 3 to 4 minutes on each side, or until it is just springy to the touch, for medium-rare meat. (Or steak may be broiled on rack of a broiler pan under a preheated broiler about 4-inches from heat for about 3 to 4 minutes on each side for medium-rare meat.) Transfer steak to a cutting board and let it stand for 10 minutes. While the steak is standing, in a large skillet heat oil over medium-high heat until hot, add bell peppers, onion and garlic; sautÈ the mixture, stirring, for 5 minutes, or until bell peppers are softened. Remove from heat and stir in the cilantro and limejuice; season with salt and pepper to taste. Slice steak thin across the grain on the diagonal and arrange slices on a platter with vegetable mixture. Drizzle any steak juices over entire mixture.