We are installing a stove vent and have broken through the outside wall of brick. About 4-5 vertical bricks came out, accidentally, over the vent hole. These bricks are the very top layer of brick for the wall so they are not load-bearing. The hole is about a foot wide and maybe 5 inches tall where the vent will go. How should I replace these vertical bricks? I was thinking of placing a steel sleeve in the hole and then putting my vent in. Will the steel be strong enough to hold the brick up? Any thoughts are greatly appreciated!