The nuts on the o2 housing to turbo are a pain. You can get to them with a standard lenth 14mm wrench though. And gutting the precat was a pain too... I hope you have an air chisel. Otherwise, it might take you a while...
Don't forget the nut that holds the bracket on the precat (rear) to the engine mount bracket... the heat shield bolts are 12mm... I can't really think of anything special about it, just don't get frustrated...