In a medium bowl, whisk together juice, brown sugar, ketchup, soy sauce, broth, ginger and garlic until combined. Reserve 1-1/3 cups marinade for basting. Cover and refrigerate. Divide remaining marinade between two large resealable plastic bags. Add 12 chicken thighs to each; seal bags and turn to coat. Refrigerate for 6 hours or overnight.
Drain and discard marinade from chicken. Moisten a paper towel with cooking oil; using long-handled tongs, lightly coat the grill rack.
Grill chicken, covered, over medium heat for 6 to 8 minutes on each side, or until internal temperature reaches 165 degrees F.; baste occasionally with reserved marinade during the last 5 minutes.
Notes
Serve chicken with fresh slices of pineapple (grilled is amazing) and sliced green onion, if desired.