Hey Teer - I've done a similar smoke, and you do have to watch the fuel more closely. How big is the butt? A heavy shoulder can take forever in winter! Maybe even split it into two smaller pieces if it's a biggun. I can't recall if you have a WSM or will be using a kettle. Either way is doable. If it's a kettle I would lay in a 2X2X1 snake all the way 'round, and light seven or eight coals to get things going. Easy to add to the tail of the snake as needed, and the temps should stay level if there's not a lot of wind. Same for the WSM, but I would just do the normal minion and leave the vents open. You will have to add coal from time to time, but not for five or six hours at the most. If it was me, I would start things up Friday morning to avoid the all-nighter when the temps really take a nose-dive. Last thing you want is to wake up to a cold smoker. Been there. Find a way to protect the kettle from wind if you can, or insulate the whole thing somehow. It's on my list to build a box of some kind this year for just that reason. You have my permission to take the day off Friday and get 'er done! No harm in reheating pulled pork the next day.