This sounds like something I would have attempted in my college/post college days. I hope this works out for you!
Some thoughts. (If any of this was covered, my apologies, I did read through this, but may have missed it)
A generator will get very old, very fast. You will seek out electricity fast. Maybe a T-pole (temporary meter box pole) which leads me to the next question.
Where are you going to park this? Do you have land? If you did, I would think you would build a cabin to park a green machine in front of. Maybe I missed the parking part.
Think of solar (in the summer, of course) and an inverter to run most stuff. Get a good quality pure sine inverter so it doesn't fry your cell phone and laptop batteries. Get a big bank of batteries and fill the roof with solar panels. Back this up with generator or electricity in winter.
Your lack of a toilet is going to make any potential girlfriend sleepover impossible. Plus, like the generator, it will get really old really fast. Look at the Natures Head composting toilet. (I have been planning an RV build on a 923 since I bought it, so, you are welcome to any of my research). The toilet is $1k, but the reviews (lots and lots of them) are dang near 5 star. It's hard to imagine spending $1k on a toilet, until you get frostbite on your weenie in -40 weather.
Your aversion to propane only leads you to other choices that are more dangerous than propane. For safety sake, rethink the propane idea. There is a reason natural gas is the standard in houses and RVs. Anything that burns can cause problems. Just be safe.
No water? Or did I miss that part? You can run Pex on the inside of the walls for plumbing (visible from inside of the house). Once again, no water will get old really fast. Where will you shower? Friends house? That won't last long.
Your idea of living in the truck is cool. But make yourself comfortable or it will get really old, really fast. Water, toilet, propane. Three things that make life easier. I feel like you are justifying skipping these items because other houses in the area don't have indoor plumbing. That doesn't mean they are easy to live in. I doubt they are nice houses, not something you would intentionally build for yourself.
Good luck with your project.