Remove the membrane, or silverskin from the bone side of the ribs.
Lightly salt both sides of the ribs. Allow ribs to rest for 10 minutes.
Sprinkle 2-4 tablespoons of rub on each side of ribs. Massage rub in with your hands. Make certain rub gets on all areas including sides. Allow ribs to rest another 10 minutes.
Start grill and turn on all burners on high so grill can preheat and grates can get hot.
When grill reaches 500 degrees, turn off two burners. Turn the last burner to low. Place one wood chip packet directly on side with burner still on. Packet should be below grate sitting on heat diffuser.
Place ribs on grill grate bone side down. The ribs should be over the burners that are turned off.
Close lid to grill and monitor temperature in grill. The temperature should be 250 degrees. Keep adjusting one burner until 250 degrees is maintained.
After 30 minutes open grill and add second wood packet. Close lid and monitor temperature to keep at 250 degrees.
After 2 hours, rotate ribs. If cooking two ribs, switch places of ribs. If cooking three ribs, rotate outer ribs and keep rib in middle in same location. Close lid and monitor temperature.
When 3 ½ hours have passed, check to see if ribs are done. Test for doneness by using the fold test. Use a pair of sturdy tongs and grasp ribs. If the meat begins to separate at the fold, the ribs are done. All the ribs I cooked have taken 4-41/2 hours to cook, but l like to check at 31/2 hours just in case.
When ribs are done, remove ribs to a baking sheet and cover and seal with foil. Allow ribs to sit at room temperature for 15-30 minutes.
Slice ribs into individual pieces. I find it easier to flip ribs bone side up so I can see where to cut.
Serve while still warm, but not hot