Any pork, but butts are the norm. Pecan or hickory bark has no color only taste, save the exotics woods.
My secret, always cook it a day ahead and let it set over night in some finishing sauce. My new favorite is Chef JJ;s available using the search engine. Pulled pork is pulled pork, ok? What do you taste, the bark, the liquid nectar of the rendered down fats and connective tissues, That's about it. BUT cook, cool and pull the add a bit of JJ's finishing sauce and bag and cool overnight. Those spices mix with the butt to form something you'll not normally taste in a pulled pork and your taste buds (and budettes), will be dancing the happy dance of ecstasy !!
You can serve it the same night with a little of his sauce, but for the optimum experience, come back the next day, warn it up in a crock pot or chaffing dish, and use a smidge more if the moisture needs a bit of equalization.
Its sort of like cooking a prime rib then adding a piece of a compound butter on top to serve. Just takes it to the next level when you have all the basics under control.
I rub with cayenne, paprika, garlic, and onion, wrap and chill for 2 days, pull then re-rub plus add salt and brown sugar to throw on the grill. ! don't foil, I smoke at 220-230, usually its a 20 to 24 hour smoke to reach 203 IT (pulled pork), and I usually use pecan but I also like hickory
I always double check for doneness with a toothpick, icepick, fork, or look for break over on ribs. Technology is great, but us cavemen still don't trust batteries.
That's my humble opinion. But you need to cook it your way, That's the only way to ensure a great piece of meat.
Bon Chance, and remember to enjoy the smoke.... it smells so good.