Stir 1 tablespoon barbecue seasoning into barbecue sauce; cover and chill. Sprinkle brisket with remaining 7 tablespoons barbecue seasoning. Wrap meat tightly in plastic wrap (wash hands), then chill 8 hours.
Cover wood chips with water; soak 1 hour.
Preheat charcoal grill on medium. Push coals to sides and place drip pan in center; pour water into pan*. Sprinkle one-half wood chips over coals. Remove brisket from plastic wrap and place fat-side up on grill rack above pan. Cover and smoke 3 hours or until brisket is 165°F, adding remaining half wood chips as needed.
Wrap brisket in foil and return to grill. Cover and smoke 1–2 more hours until brisket is 190°F to 195°F (for shreddable). Add coals and water as needed to maintain temperature and moisture.
Remove brisket from grill. Cover and let stand wrapped in foil 15 minutes. Slice across the grain. Microwave barbecue sauce mixture 1–2 minutes until hot; use to coat brisket. Serve.