Preheat grill to 275℉.
Season all sides of pork belly strips with Texas-style rub or all-purpose seasoning of your choice.
Place the seasoned pork belly strips on the heated grill fat side up, and smoke at 275℉ for about 3 ½-4 hours, or until the pork belly is probe tender and the internal temp is about 200-210℉. About 2 hours into the cook time, flip the smoked pork belly to cook fat side down.
After the pork belly has been cooking for about 2 ½ hours, prepare the bourbon citrus glaze. Combine all glaze ingredients in a medium saucepan, and heat over medium heat just until boiling. Then reduce heat and simmer for approximately 1 hour.
Remove pork belly strips from the grill and allow to rest on a cutting board for about 10 minutes before cutting into 2” cubes.
In a large bowl, toss the smoked pork belly with about 1 cup of the glaze and the resting juices from the cutting board. Then transfer glazed pork to a wire cooling rack, and put back on the grill at 275℉.
After putting pork belly back on the grill, transfer the remaining glaze from the bowl to the saucepan, and reduce over medium heat until it is a thicker consistency. This will be your basting glaze.
Once the pork belly is back on the grill, smoke for an additional 45 minutes, basting every 20 minutes with the remaining glaze.
After 45 minutes, remove the pork belly burnt ends from the grill and transfer to a serving platter. Drizzle with the remaining reduced glaze. Top with orange zest and serve.