Depending on where you are, you might want to consider investing in a trip to the Docks by road and speak to the people who will be handling this as well as having a good site recce. If you treat it like the confined area (5S recce) it is, you will have a much less exciting arrival than turning up in a 500' hover trying to figure out where all the cranes, wires, hazards and blowy stuff is. I know it takes time, but I'm assuming a 109 is a reasonable investment for somebody, so its a good trade off.