This is what I have always done. I apply about 1 tsp of olive oil on the meat and rub it all over. Then put the rub on it an place it in the smoker. I have done the overnight rub but have never been able to tell a difference. Then smoke at 225 for about 14 hours. I have never seen my taylor temp gauges hit 195. They have always been 185. I simply open the door at 14 hours and pull on the bone. If the meat separates from the bone, then the butt is done. Wrap butt in foil and put in dry igloo cooler for 1hr,pull apart,apply smokin okies finishing vinegar sauce,consume.
A rub should be 1 part salt,1 part sugar, 1 part spices