Preheat oven to 350°F. Cook bacon, then remove from pan, reserving some of the grease. Sauté onion and celery briefly in a small amount of bacon grease until soft. Mix all together, except for crumbled bacon and bread. Spray loaf pan with cooking spray. Place bread on bottom of pan. Spread meatloaf mixture evenly in pan. Cover with foil and bake at 350°F for 1 hour and 20 minutes. Remove from oven and drain carefully. Spread with honey barbecue sauce and crumbled bacon. Place in oven for about 10-15 minutes, just enough to glaze. Remove from oven, let stand for 5 minutes.