Due to the angle of the trailer in you photo, it is hard to tell how much trailer sits out behind the axle. Having said that, loading the trailer heavy to the back end will decrease your tongue weight.
I hauled this load of wood a few weeks ago with my 104. That trailer is has a 6'X12'X2' box on it and the load was rounded over. I started with the tongue weight pretty close to neutral, but had to add some weight back to the front to get traction in a few spots.
http://s673.photobucket.com/user/oak...zed_1.jpg.html