Goal difference wont come into it. We're never going to catch West Ham or Watford's and we will need to finish above one of, maybe both of them.
It's pretty simple, we need probably 7 points, possibly 9. If and its a huge if, but if we get to a stage where beating West Ham keeps us up then I would actually be pretty confident. We would have nothing to lose, all West Ham can do is bottle it. But that's a convo for another day.