"This is how I do it at the Commissary, raised up so the smoke is closer to the exhaust vent to eliminate any widening of the smoke screen and up high enough to clean it out, load it and monitor it as needed.
It cooks overnight most of the time and then I take the Food Truck out next day to feed the public.
FYI... I had to leave the wheels on and they are buggied onto the back real tight so it won't move around.
Had to do that because when I smoke 120lbs of pork shoulder that 6" full hotel pan you see underneath becomes my drip pan because the one that comes with it is not enough space to catch the drippings when smoking overnight.