Sprinkle pork with salt; cover and chill 30 minutes.
Prepare charcoal fire with half of charcoal in grill; let burn 15 to 20 minutes or until covered with gray ash.
Push coals evenly into piles on both sides of grill. Carefully place 2 hickory chunks on top of each pile, and place food rack on grill.
Place pork, meaty side down, on rack directly in center of grill. Cover with lid, leaving ventilation holes completely open.
Prepare an additional charcoal fire with 12 briquets in an auxiliary grill or fire bucket; let burn 30 minutes or until covered with gray ash. Carefully add 6 briquets to each pile in smoker; place 2 more hickory chunks on each pile. Repeat procedure every 30 minutes.
Cook, covered, 5 hours and 30 minutes or until meat thermometer inserted into thickest portion registers at least 165°, turning once the last 2 hours. (Cooking the pork to 165° makes the meat easier to remove from bone.)
Remove pork; cool slightly. Chop and serve with Cider Vinegar Barbecue Sauce or Peppery Vinegar Sauce.