Start your smoker and heat to 250 degrees F. When the smoker has reached temperature, add chunks or chips (depending on your smoker type) of the apple wood.
Trim most of the fat cap from the pork shoulder
Completely cover the pork with Philly Grit
Place the pork in the smoker, and insert a probe thermometer to monitor internal temperature.
Smoke until the internal temperature reaches 195 - 205. Test for doneness by pulling on the bone. If it easily slides out of the meat - it is done. Be patient, the pork may take 10 hours or more depending on the size!
When the pork is cooked, wrap tightly in foil for at least 30 minutes.
When ready to serve, pull the pork apart with two forks and serve as-is with barbecue sauce on the side.