Not sure where I originally found this one, if you know, drop it in the comments and I can update my page : )
2. Roast for 3 hours in the preheated oven. Remove from the oven and carefully turn the bird so the breast side is facing up. Return to the oven and cook until the internal temperature of the thickest part of the thigh has reached 180 degrees F (82 degrees C). Allow the turkey to rest for about 30 minutes before carving.