Thermapen MK4 - Highly recommend everyone have one of these to check the meat temperature.
B&B Apple Pellets for pellets smokers
Kingsford for grills is my goto with a small piece of applewood chunk.
Cook at 300 degrees on INDIRECT HEAT till they get to 145 degrees. Usually takes 30-40 minutes. Once they are done, take off the grill, remove skin, and dunk in warm BBQ sauce. Put back on a cedar plank and in the grill for 5 minutes to set the sauce. Take out and serve them while warm.