In a large saucepan, heat 4" water to boiling over high heat. Trim off 1" from the tops of peppers and remove seeds. Coarsely chop tops, set aside. Add bell peppers to the boiling water. Cook 5 minutes, drain, set aside.
In a large skillet, heat the oil. Saute onion, celery, garlic, and reserved chopped pepper tops until golden.
Stir in kidney beans, olives, if using, and corn. Stir cornmeal and chili powder into stewed tomatoes. Add into sauteed vegetables. Heat to boiling, stirring occasionally. Simmer 10 minutes.
Divide the chili mix into prepared bell peppers. Sprinkle the cheese and crumbled corn chips over tops of peppers.
To bake, arrange well drained peppers upright in a 9" cast iron skillet or shallow baking dish. Bake 20 minutes or until filling is bubbly and topping has browned.