I just recently made my first pulled pork (boston butt), 17 hours seems like a long time to only have one piece in there, especially because its easy to freeze pulled pork and eat it later. My question is do you put the second (or third) butt on a rack above the first. My thought about doing this was that a lot of drippings from the top one would fall on the one below it and may not form the nice bark or would cause a grease pile on the one below it.