[Observer]

Here are different pieces you will have to reassemble:

Part 1:
http://www.filefactory.com/?c79722

Part 2:
http://www.filefactory.com/?a7ba45

Part 3:
http://www.filefactory.com/?59209b

Part 4:
http://www.filefactory.com/?9d8bcd

Or you can try this link for the entire thing:
http://www.subsim.com/~subsim_mods/downloads_tonnagemod.php