I agree with Dave. 9 - 12 hours is a bit short, unless you're planning on using foil (yick). Don't use foil - allow yourself the extra time and you'll be very pleased with the results. When you can wiggle the bone and it feels like it could be pulled out of the meat easily, when the meat looks like it's "caving in" on itself, and when it wiggles and giggles when you poke at it, then it can be considered done.
I usually put a butt on around 8 at night, and pull it around 10 - 12 the next day. Some butts are quicker cooking than others, though, so remember that you can't go by time alone.
As far as a mop, the
Southern Sop recipe can't go wrong. Also, the SmokinOkie out of Ponca City OK has several that I really like as well, especially his apple-juice based "Smokin's Pulled Pork Baste & Serving Sauce ". You can go to his
Cookshack Smoker Bulletin Board here , and see links to his "Smokin Okies Vinegar Mop for Pulled Pork", "Smokin's Pulled Pork Baste & Serving Sauce", and "Smokin Okie's Virgin Mustard Sauce". I'd post the recipes themselves, but I'll ask his permission first before I put them over in the recipes section.
Keri C, still smokin' on Tulsa Time