8 hour butt

If you had to cook a 10lb pork butt in 8 hours how would you and could you do it? There is a local contest that is going to be held here in my small town, the thing is they don't know bbq so they have check in at 9am and turn in at 5:30 for butts and 5:00 for ribs.:doh: Ribs I can do but this...