Let me just say this...mep1811 has been all over the world and Alaska is a place of the many he will enjoy with his new trailer and Landcruiser. Having said that his Landcruiser is looking very nice!If you've previously made this trip, then I'm curious why you think you'll need all this extra gear. The road isn't technical, there are enough fuel stops that main tank + auxiliary should give you plenty of wiggle room. All that stuff on your roof rack is going to get caked in mud/dirt FYI.
And where do you plan to go "further offroad?" With the exception of some minor snowmobile tracks, the Dalton highway is the only real road between Coldfoot and Prudhoe Bay.