I would inject using Dr. BBQ's beef injection and then rub as normal. Throw some bacon on top of the roasts or if you have some extra fat from briskets you can put a couple chunks of fat above the roast to baste the meat and keep moist. Use a spritzing sauce of Jack Daniels, or whiskey of choice, and apple juice, and spritz every 45 minutes or so. After a couple hours in the smoke I would move to a foil pan and put some juice and some beef base in the bottome of it to keep it from drying out too much. I'd pull off the grill at internal temp of 195 or so.