Thats a pretty big job there. Those are a PITA when it comes to the upper intake plenum, you've never seen so many things attach to an intake before. Without going into a ton of details on this engine, one main thing would be the timing belt, tensioner, waterpump and timing belt idler. Be prepaired to replace all of them. MAKE SURE you time the camshafts and the crank BEFORE putting the heads back on. You'll bend a valve in a heartbeat.
I believe the book time on a job like this is 14.8hrs and it takes almost all of that
