I have been pulling 5th wheels for the last 10 years and have went back to a travel trailer. I am having a heck of a time getting it level. Seems I get it level disconnect get it level up and down an...
I don't worry about it too much if you're slightly off level. I level the trailer side to side. Then unhitch and level front to back. Stabilizers out and then slide out, only have a single, large slide. If the trailer goes slightly off level where the slide side is lower, no worries as rain gets directed at the edge of the slide and not towards the slide seal.
You trailer does not have to be perfectly level, pretty much just close enough to level is fine.