Option #1.
Keep the Ram. Outfit it with a cap, rooftop AC, hot water, and solar. Or consider a FWC or Bundutec camper.
Long trips and slab, are always best in a fullsize. That truck is going to get really small, really quick.
A rust free XJ is awesome, but $5000-7000. +$2000 to swap in a junkyard manual transmission. +$2000 to install a Ford 8.8 rear axle. +$2000 to weld up the boxes as needed.
The XJ is like a cool 80's square body GM truck or suburban, before they went all globalhomo. We remember how much fun they were, but forgot that we custom swapped the engine, trans, and both axles out of them.
I'd sell my XJ for... IDK... prob $10k as it sits. It's mostly rust free (passenger side drip-rail has rust, as does the driver's floorpan because an idiot previous owner ran lightbar switch wiring through the driver's door jam weather strip), has frame stiffeners, Dana 44s front and rear (with 5.38s and E-lockers), new 1-ton steering, the really nice ball joints (I think they're Teraflex, but don't remember exactly, I need to go out and look lol), long arm front, nice Fox shocks all around, armor, I just put $2500 into a very nice stereo in it, etc. etc. etc. That said, it's a 50/50 rig: it looks great from 50 feet or going by you at 50 MPH. But look close and it's about 7 different shades of white and has lots of dings and scuffs. The interior is actually pretty darn nice though.
The xj is unibody. It'll tear the suspension from the frame "boxes". If you can't weld, you will soon.
Yeah, because nobody has ever built and beat the ever loving tar out of XJs successfully...
Seriously, it's probably the heaviest abused platform in off roading. Yes, if rust gets to them it can be an issue... but tell me full frame Tacomas aren't worse. Sure, they tend to get unibody cracks around the steering box... but tell me full frame C10/K5s don't do it worse. The XJ is an amazing, amazing platform on a budget. The problem is people figured that out probably 20 years ago once the early ones were hitting ~20 years old and were cheap on the used market so most XJs have already been beaten on by 4-5 owners at this point. WJs "are the new XJs" IMHO. The unibody in the WJ is actually far stronger but if they're from the rust belt the rear lower control arm mounts will rip right off. It's just the reality of any ~20 year old vehicle that's been driven in road salt its entire life: there will be problems. Of course, it seems like people are catching on to the WJs and it's getting harder to find a cheap, clean one. If you take your time and look around you can get a heck of a budget Overlander/DD for ~$5k.
-TJ