Rub
Mix sugar, paprika, chili powder, onion powder, garlic powder, cayenne pepper, salt, and pepper in a bowl.
Sauce
Whisk together ketchup, sugar, vinegar, molasses, Worcestershire, chili powder, paprika, onion powder, garlic powder, cayenne pepper, black pepper and 3/4 cup water in a 4-quart saucepan and bring to a simmer over medium heat.
Cook, stirring until thickened, for about 20 minutes.
Remove from heat, measure 1 cup into a bowl and stir in 1/4 cup honey and the apple cider vinegar. Set aside. Reserve remaining sauce. Pour apple juice into a spray bottle and set aside.
Prepare the Ribs
Brush oil on ribs on baking sheet and sprinkle with this rub. Let the ribs sit 1 hour.
Prepare your grill using apple wood chunks or chips. Place ribs meat side up on grill grate. Maintaining a temperature of 225 degrees to 275 degrees, cook spraying with juice every 30 minutes for 3 hours.
Remove ribs from grill and transfer to 2 large stacked sheets of foil. Drizzle butter, honey and sugar evenly over both sides of ribs. Position ribs meat side up and close foil around ribs. Return to grill and cook for 2 hours.
Uncover ribs and discard foil. Return ribs to grill and cook, basting with sauce after 30 minutes, until the tip of a small knife slips easily in and out of the meat, about 1 hour. Serve with remaining sauce.