Having cooked two 7.5 lb bone in rib roasts just yesterday: Here is what I did.
I rubbed down the meat with generous amounts of freshly ground pepper and kosher salt after I rubbed it with rosemary (she didn't mind a bit)
Then I doused it with Worcester sauce and wrapped it and let it sit for about four hours. (had I been prepared this would have been longer.)
I let it sit on the kitchen table for about 4 or 5 hours before it went in the cooker. The internal temp was 54 degrees when the cooking started.
I ground on more pepper and put one in the smoker at 250. Thirty minutes later I put the second on in as well as the smoke box.
In the smoke box I had a couple chunks of garlic, some dried rosemary, about 2 ounces of hickory and one ounce of cheery.
It took about 3 ½ hours to get the first one to 118 which is what I chose based on everything I've read. This came out... wrapped in foil and towels and rested in the cooler for 30 minutes. Then it came out and opened up and put in the oven at 500 for 20 minutes to crisp up the fat. Out of the oven it came and covered up with a piece of foil for about 20 minutes prior to the knife.
The other one followed the same routine only the internal temp was taken up to 128 prior to removal from the smoker. It was surprising but I really didn't appreciate any significant difference in the two.
I left the temp on 250 at all times.
The above instructions are my interpretation of the various posts and recipes I've gleaned from this forum. The meat was wonderful.... It is a great starting point. I dare say it is a foolproof way of cooking ˜prime' rib and a great way for the novice to start out.
I never use recipes per se.... I do very little measuring and I don't take notes. I think the key points here with the rib roast are: Salt and pepper and ROSEMARY and internal temp of 118. Oh... don't forget a great piece of quality meat to start with.... Mine was Choice Herford at 10.99 a lb...