Can I recommend a couple of mounts that you could use.
I would pick up a clamp mount (super versatile - one of my favorite mounts in fact!) and a suction cup mount for attaching outside the vehicle.....
You'd get some really cool shots on those trails!!
You could probably do with a small action camera as well, mounted to the front of the vehicle and capturing a hyperlapse maybe?
Very envious - wish I had trails like that near me!! lol