Hi everyone! I'm newer to smoking and this is going to be my first time smoking 3 pork butts. I got a new smoker ( weber smokey mountain 18"). I have a few questions. 1) I read that a general rule for cook time is 1.5 hour/lb (of course IT will tell when to pull). I am smoking three 7lb butts. Is the cook time going to be based off 21lbs or just 7lb? 2) Would the cook time be the same for unwrapped because I do not plan on wrapping? 3) Any advice on how to hold temp through the night would be helpful! Any advice would be greatly appreciated. Thanks!