Rinse pork roast, and pat dry. Inject top of roast at 1-inch intervals with Pork Butt Injection Marinade.
Coat roast with Pork Butt Dry Rub, pressing gently to adhere rub to pork.
Light one side of grill, heating to 250° (low) heat; leave other side unlit. Place roast over unlit side, and grill, covered with grill lid, 7 to 9 hours or until a meat thermometer inserted into thickest portion registers 190°, maintaining temperature inside grill between 225° and 250°. Let stand 15 minutes. Slice, shred, or chop roast.