I found 2010 Mini Cooper seats at a pick n pull for $125. (No more ZJ or WJ seats in my area.) Here's the fab thread for how I installed them.
Remove the Mini seat belts and track sliders, ditch them first if the yard wants to charge extras. There's no way to get Mini seat heaters to work outside of a Mini. Skip the heated seats and add a Dorman heater if you want.

1. Pull XJ Seats and sliders.
2. Remove seats from tracks.
3. Make brackets for passenger seat, keeping the Mini seat height adjuster. 1" square stock and 1.25" angle iron, ~20" of each.
4. Bolt 1" square tube to the rear seat mount. Shorten the front adjuster seat rails by 1" and weld the angle iron to the seat rails.
5. Cut height adjuster off the driver's seat, remove the lower seat cushion, weld 1.25" angle stock to the seat frame front and back. Make a Z bracket in rear and a square section up front.
6. Bolt everything back in.

Height and rake are pretty good, butt feel is now modern. Easy enough in and out.

 

Cherokee seat mounts are 14" x 11" rectangular pattern, longer front to rear. The passenger seat gets a 1" square tube in the back to the Jeep sliders and is sloped to fit the floor hump. 9/32" holes for adjustment slop.




The front seat mount needs to be cut down a bit to no be so tall at the front. Weld a 1.25" angle iron piece inside, 3/4" of an inch below the existing bolt holes in the seat runners. (I used a piece of 1x lumber and a flat bar to hold the angle stock in place.
Cut the seat bracket off below the angle iron. Drill a 9/32" hole for the front slider close to the runner, leaving just enough room for a 10mm nut to hold it to the Jeep seat slider. It will need to be 14" in front of the existing hole at the rear of the runner.
You'll need to drill another 9/32" hole in the inboard seat runner to match the hole on the outboard, Mini had them staggered a bit.
Not shown in the photo, drill a last hole 11" over from the first in the angle iron.
Passenger seat mounts pretty much like the original Jeep seat.

 

What is the size difference between these and OEM ?

 

Driver's seat needs to be stripped and the adjuster arms cut off. The vinyl cover unclips from the bottom, it's fairly easy to remove. Here's a deconstruction process from a R53 site, https://www.specr53.com/blog/diy/min...deconstructed/ DoobTube also has a few videos.

a. Crank the adjuster all the way to turn the arms for full elevation.
b. Remove the height arm, pivot cover and side cover. (Watch some videos)
c. Remove the seat lower cover and cushion.
d. Remove the torsion springs from the two round seat tubes, they pop out easily.
e. Cut off the adjuster arms, and drill out the rivets for the height adjuster assembly. Turn the arms back up into the seat.

I made a box section and welded it to the front, a better way would be to weld a 1.25" angle iron piece to the front and back, then bolt two more pieces on to get some height adjustability. I did this in the back.


Drill the Z brackets 9/32" to fit the seat as needed, the seat adjuster cover in the lower left corner wants to rub into the Jeep seat belt cover, so installation needs to leave room for that. Replace the seat cover and trim.

There will be a hole left from the mini height adjuster, fill that with whatever coaster you lifted from a taphouse last week.

Notes:
Airbags have been left in, the other seat wires are cut out.
There's really no way to fit the height adjuster in the driver's side with the transfer case hump.
Seats look a bit bigger than stock from outside, but are not as big as the Corbeau Trailcat seats I was thinking of installing.
It took two afternoons to fab and install.
Some of the driver's seats in junkyards are getting worn out now. Pull covers from passenger seats, panels can be deconstructed and added into driver's side covers pretty easily by an upholstery shop for less than full covers.

 

The height is just about the same, floor to seat. Seats are narrower, or feel narrower from the bolsters. Headrests are definitely higher and more forward, but they are not obnoxious like the most recent 2018+ cars have gotten.

 

Original Seats. New headrests are 3" higher than the factory ones.

 

Nice, Always love to see people finding different seats to put in their XJ. Especially when they show HOW they did it.

 

What is this mania for replacing XJ seats, which I think are far better than average?

 

I am kinda with you on this.
OK my one piece manual cloth buckets were so so.
But I once I got the factory heated/power removable headrest seats in both sides of my '00 I was more then happy.
No need IMO to upgrade after that.
Except that I would like to find the color correct seats for my '00.
You really can't tell cause of the CoverKing Rhinohide seat covers but those are Agate seats in front.
And they really should be Camel.
LOL.

 

Mine were GARBAGE after about 5 years. Put WJ seats in it and now have PRP reclining suspension seats.

 

I had a WJ briefly, the seats were nice (black leather) but they were nothing special & going back to the XJ I didn't notice anything lacking (all of mine have power seats - leather in the '99 Orvis -; don't know if that's part of the Limited package or because they're export models).

Curiously I now have a KJ DD & when I first got into it I thought "Mmmm, nice seats (black leather - again) so if I was thinking of a seat swap, they're what I'd be looking at ('cos the WJ certainly didn't have that "wow factor) but maybe the reason you never hear of this swap is because it's not really practicable.