I live in an area known for its barbecue, and I try to eat at least one pulled pork sandwich every week. One good thing about using Boston butt as a pulled pork roast is that it's a very inexpensive cut of meat. It may have a fair amount of fat, but most of that is rendered off during the slow cooking process. I like to slather a good amount of pulled pork rub all over the Boston butt roast, then pour some liquid smoke in the pan and wrap it all with aluminum foil.
If you can't find a good commercial pulled pork rub, then you can use seasoned salt, dry oregano, dry basil, garlic powder and black pepper. My suggestion is to be very generous with the rub, since it needs to work its way past the fat layer and into the meat.