Piney has it right. The only other question you need to answer: slice or pull? If slicing, I foil at 165* and take the meat to 185-195*. If pulling, I foil and take to 205* -- it will literally fall apart in your hands. Either way, when it hits temp, Leave the foil on & wrap in towels and place in a cooler to rest for NO LESS than 1 hour (2 is even better) before slicing or shredding. The meat will stay nice and hot for a very long time this way, so don't worry about waiting that long before you serve everyone. In fact, you will burn your fingers a bit shredding the meat by hand.
BTW, I never bother to brine, and the smokey goodness never lasts very long ;-). I also don't spritz with any moisture, but I do keep a pan of water in the smoker to keep moisture levels up and smoker temps stable.
I've had them finish up in about 9 hours and had them go 14. It's done when its done. Things vary so much because of the differences in connective tissue content, which leads to a brief discussion of "The Stall." The internal meat temp will stall around 145* and may stay there for hours. Don't panic, and don't keep peeking! That connective tissue is breaking down which gives you that tenderness and fantastic flavor. Keep the thin blue smoke going and cook temp in the butter zone (225-250*), and all will be well. Your first stall is the worst, because you convince yourself your doing something wrong or missing a trick. Think of it a little like "trial by fire."
Cheers! Follow Piney's guidelines and my advice, and you'll be stuck doing this EVERY Mother's Day, so I hope you like doing it!!!
