For the turkey: Preheat the oven to 325 degrees. Paint grill rack with clarified butter. Place the chestnut dressing in the neck opening, pressing it in firmly. Place the pork dressing in the rear end. Truss the turkey. Lightly flour breast. Place the turkey on its side on a grill rack in a baking dish and bake for l hour. Turn the turkey onto the other side and roast for 1 hour. Turn the bird breast side uppermost and paint with clarified butter and season with salt and white pepper. Roast for a further 2 1/2 hours basting every 30 minutes with clarified butter.