If you're gonna cube it and brown in oil, than anywhere around 140 or so. If you want to pull/ shred it, than take it to 160 than foil till probe tender or a fork twists in like spaghetti.
If your not going to cube it, may I suggest after smoking it, throw it thru a meat grinder. I do that with my left over brisket, and it makes great chili that way. The consistency is different, but I have received rave reviews on mine.