Heat oven to 350°F. Bake loaf as directed on can--except brush with beaten egg and sprinkle with poppy seed before baking. Cool; cut in half lengthwise.
Meanwhile, cook hot dogs. Set oven control to broil. Place hot dogs on rack in broiler pan. Broil with tops 4 to 6 inches from heat 3 to 5 minutes, turning frequently, until hot.
Place hot dogs on French loaf halves. Top with relish, peppers, cucumbers, pickles and onion. Sprinkle with celery salt. Cut each in half to total 4 open-face servings.