Roast Turkey With Sage, Onions, and Giblet Gravy without wheat

2 loaves Italian bread, loaves 1/2 pound of day old bread, cut into 3/4-inch cubes (about 12 cups) or 2 loaves French bread, loaves 1/2-pound of day-old[...]

1 tablespoon olive oil 1 (12 -14 lb) whole turkey, neck and giblets reserved 2 medium carrots , chopped 2 large celery ribs , chopped 3 1/2 cups chicken broth[...]