Finally got the bunks done enough to take the first group trip. I was able to comfortably transport and sleep me and 7 friends 260 miles one way to my fishing property! Everyone had a great time compared to other years when we took multiple small vehicles. The experience is well worth the 9.75 mpg we got (ouch).
The bottom bunks are 6 inch foam covered in duck canvas with bed sheet toppers, the top bunks are 4 inch foam covered in the same stuff. Everyone slept really well and was comfortable except for the 2 guys on the floor.
I installed a Power hungry performance Hydra tuner before we left. That helped me maintain 65 mph with reduced EGTs than before the tuner, and gives me much more usable power for easier driving. I ran most of the trip in the 40 Horsepower setting which seemed to be the most comfortable for the engine. I loaded a tune for up to 140 extra horsepower which I ran for a bit and it really moves the 12k lbs loaded weight well. EGTs were not happy with that tune though.
I installed a remote mount transmission cooler with a fan (derale 25 row) and was able to keep the temps well below the danger zone. The highest I saw pulling a long hill was 185 degrees. Before the cooler I would routinely see 210 degrees...
Overall I am extremely pleased with how it works. There are a few minor things I have left to do, Trailer hitch, aero mods for hopefully more MPGs, floor corner trim, more sound deadening to make the driver area more comfortable, and some carpet runners for the floor.