A quick note about carrying tools, its pretty important to have actually
used the tools you carry. I carry out all my maintenance, repairs, and upgrades using only the tools I have in my rover. If I can't work on the rover in my driveway with those tools they certainly wont work out in the mountains.
In the rover I have a set of drawers (Hastily built before a trip and needs to be replaced) in which I keep the left drawer filled with any bulkier tools, spares, and an old ammo box filled with all my wrenches and sockets. (some smaller spares as well as recovery gear is in the right hand drawer)
And in addition I bring along my work peli-case for any longer trips that I just chuck in the back (Due to my line of work it contains tons of useful bits for quickly diagnosing and fixing problems).
(Not my rover, but to explain how it just gets tossed in the back)