NO brine. You don't want to risk making hammy BBQ. That bad boy is full of flavor on it's own. Only bother with injecting flavor if (A) you're not happy with your product or (B) whoever is eating your food is only gonna eat one bite or two and ya wanna wow them for some reason.
Just rub and throw her on the smoker. As a matter of fact if the rub I wanna use has salt in it I will NOT ever let the rub sit much more than an couple hours before it's on the smoker to keep from having a hammy pork butt.
Just my opinion....ain't tellin ya to do a thing ya don't want to.