[RMcNeal]

I have only left the rig hooked up overnight once. Mine rides a bit nose high, so in order to level and open the slides, the back tires were off the ground on one side because the site was not very level.
I usually just unhook so I can refuel the truck without the rig anyway.
If you do stay hooked up, DON"T do the auto-level. The nose of the rig drops very low and then the sequence to level begins. That could be very bad if your truck were in the way. You can manually put the front legs down just enough to lift the weight off the truck a bit. The put rear legs down to to get level front to back. Adjust left or right to level side to side. All this can be done through manual control as the panel shows you how close to level you are as you adjust.