I will post some interior shots over the next couple of days so you can see the answer to your question.. You cannot achieve 5 seats, massive storage drawer, extra 40 litres of fuel in a sealed unit (wait to see pics on this one), 70L water tank, 47L ARB fridge, massive slide out kitchen and sleeping for 2 Adults and 3 kids up top! (although the kids sleep in a ground tent normally) when the trucks a rockin, dont come a knockin......
Thats what you cannot achieve with a stock truck. Believe me I tried it on a trip to the Sahara, which is why I put my efforts into this build. I get 28MPG with my overdrive on a manual gearbox from an L200 pickup (swapped it from the crappy 3 speed Auto). We had a Howling moon roof tent before this and at best even the biggest ones only sleep two nicely.