Make cornbread and biscuits the day before.Crumble cornbread and biscuits on sheet pans and let dry overnight.Preheat oven to 375.Grease 9x13 dish. Use another 8x8 dish if you have extra.Melt butter and bacon grease in large skillet and saute celery and onions until tender.In large mixing bowl, combine cornbread and biscuit crumbs.Add celery and onions and all the seasonings and stir gently.Add one quart of stock and stir until mixed well.Add additional stock until consistency is very moist but still thick.Add salt and pepper to taste.Pour dressing into prepared dish.Dot butter on top of dressing and cover with foil.Bake for thirty minutes, then remove foil and bake another twenty to thirty minutes, until well browned.