#1 rule of off-roading if you have 4 wheels*:
as slow as possible, as fast as necessary. If it gets technical, follow that religiously. In a training course I learned that even 4-LO, first gear can feel ridiculously fast sometimes.
Don't be afraid to get out and look. Multiple times if needed, to check on where the truck is, what line you want to take, and if you're about to hit anything you shouldn't be. If it looks technical, get out and look at things before you attempt them. Plan your line.
Don't be afraid to reverse. Either to try a new line, or just bail out.
A good spotter is invaluable.
60/80 pressures are definitely doable. Less comfortable so you'll be going slower, but plenty doable. If you do meet up with someone they might have a compressor and then you could air down and use their compressor to air back up. It's mind blowing how much better the ride is off pavement when aired down.
If going with other vehicles, have some form of communication between rigs. Ham radios are the top-end, but simple walkie-talkies work just fine the majority of the time. It makes things a lot more enjoyable as you can keep up a conversation, and there's added benefits when spotting or calling out a hazard for the next person.
And, of course, like hiking or other outdoor activities have some form of communications (e.g. InReach or Spot) if going out of cell range. In particular note that with the truck you can get a lot farther away from civilization a lot faster than on your own two legs, so if you break down hiking out could be a significantly more difficult proposition. Also carry the emergency essentials, just like you would while hiking, in case you need to wait for help to arrive.
* On two wheels speed helps you stay upright, so it's more of a balancing act there. Not speaking from direct experience, but seeing others.
