Remove prime rib from the fridge a few hours before you plan on cooking it. Rub with avocado oil, then add your rub and leave to sweat.
Prep your grill. Depending on the type of grill you are using, light about 1/2 a bag of charcoal, and a few sticks of smoke wood. Once the fire has eased spread out the coals into a nice even bed. When you can hold your hand above the coals where the prime rib will sit for around 8 seconds its ready.
Grab your rotisserie rod and push it through the center, then secure and tighten the clamps.
Mount spit, place your thermometer under one of the clamps and let it rotate until it reaches 125°F.
Around the 100°F mark, start brushing on the baste every 15 minutes.
Once it reaches 125°F, take the spit from the grill, place the prime rib on a cutting board, and remove it from the rod.
Tent loosely with aluminum foil and let it rest for 15-30 minutes.
Cut strings, slice the prime rib, and serve.