I’m no camper expert and idk what I’m looking at in the second to last pic, but if that’s where the issue is from the back side then idk why one would attack it from the front side.
Also as a structural engineer and part time gear head, it still seems highly unlikely that a bit of sag (can you even see a belly across the front edge of the tub when sitting on jacks?) up front would rack the back enough unless you’re compensating with one front jack for an entire camper that is twisting.
Try the first. Put camper on jacks then put a solid support under it just across the front edge, like a saw horse. Put the front camper weight largely on the support and not the jacks. If that fixes it, then I’m quite likely wrong and it may fix the door issue.
But please stop using the “it’s cheaper than $50k for a new camper” thing. That is wholly an excuse used by those who are unable to compare apples to apples. Guys do it with trucks all the time…. “$10-15k for new everything is cheaper than a new $80k diesel…” well no shart Sherlock. Now compare it apples to apples….lol. Lots of good trucks and campers that don’t have issues/have low miles that aren’t $50 or $80k…. It’s just a flawed means to justify significant expense.
