This is long-winded, but may be helpful.
FWIW, I have seats from a ~85 Mazda 626 in my 68 Fury and they have an incredible amount of travel. A 7ft-tall person could drive my car if their head fit under the roof.
But would be difficult to find a decent set of those seats at this point. Mine have been in for ~20 years.
I've done a handful of seat swaps over the years, and they are always more hassle than you'd expect.
You must put the seat tracks in a good location so that the travel range is useful.
Then must center the seat L-R versus the steering wheel, and get the other one to match.
After that - it's drillbit time. Which is when you'll find that you may only be able to use 1 original hole at most.
And laying-out the hole locations, transferring them from seat to carpet, isn't always easy when you get to doing it.
And if you don't plan/measure 3 steps ahead, you may discover that a bolthole falls on the edge of the braces underneath the car.
So you then return to moving the seat a bit, possibly needing to re-adjust the seat track locations.
And depending on the era of seats and what car they came from, you might need 2-3 different-height leveling blocks between tracks and floor. (FWD cars are better donors?)
And then there are the original holes to seal up somehow, to make sure no fumes/roadsplash seep in.
An interesting development:
I recently got a set of 2019 Chrysler 300 seats to put in another of my cars.
They have a completely flat mounting plane, presumably due to catalysts now being closer to the engine and not under the floor.
I have not installed them yet but have learned a lot up to this point, some of it the hard way.
If getting new seats, make sure to NOT get a memory seat, at least not from a Chrysler product.
Some of the seat function is in a body module, located in the car, tied to who-knows-what else. I learned this after buying them.
I had to replace the harness and switch to get the driver seat to work as a standalone. The drive motors are different (standard 2-wire DC vs 4-wire stepper motors), and not easily swapped between seat tracks. The memory switch looks the same but has 4 wires instead of 8-10 wires.
So I bought a standard PSeat track ($140), which came with no harness or switch.
So I then bought a new switch ($40) a new harness off ebay (got lucky to find a correct one for ~$100).
The tracks aren't easily removed (like the old days) without disassembling some of the track, some of it's riveted together, it's all engineered and assembled as an integral thing. So I would've had to swap the upholstery, which seems do-able as it is all held on by elastic strapping and hooks. I have no idea how the JY disassembled it.
On a whim, I tried the standard 2-wire harness and switch on the 4-wire motors and it works fine.
Modern seats may have a ****-ton of wires going to them: monitors for occupancy for seatbelts and airbags, airbags in the seat, heating/cooling functions, and feedback sensors for other stuff. Although my seats are loaded with features, my research for the correct harness showed that almost any modern seat is going to have 20 wires going to it. So - if getting modern seats, make SURE to get the pigtails with them (I was so glad I did).
The 2 circled connectors below show what I was dealing with. I was not able to find any schematics, but fortunately there were red and black wires on the pigtail that were larger gauge than all others, and hooking to them operates all the seat motion functions. These seats have fans built into them, I may try to figure them out (but the fans have 3 wires, who knows which ones to use?).
You can also see 2 of the 4 screws on the motors (circled). I loosened them and realize they hold the motor can onto the drive mechanism, and would cause the armature to come out. To remove the motor requires disassembling it from the metal drive mechanisms, which seems a nightmare. Which is why I tried the 2-wire harness on one of the motors, and luckily it worked.
So, what to look for:
Non-power seat would simplify things, but then you depend on the seat's track and adjustability fitting you and the car (esp for height from the floor).
Non-memory seat.
No seatbelt retractor built into the seat (unless you want that).
Make sure to get the pigtails.
Make sure they are from a 2-dr car! I overlooked that, as I got so excited to find a nice set of new black Chrysler 300 seats to put in an old Chrysler 300 with black interior. It might not be as big a deal in in a convertible if the top is down (they can climb in standing up), but I will need to power the seat and recliner forward for anyone to get in my backseat (a hassle). There does not seem to be an obvious way to modify the seat to pivot/latch, so apparently this frame is different from a Challenger seat. I had hoped one of the bolts at the hip could be made a pivot and the other bolt modified to a latch-pin, but that doesn't look likely. Rarely will anyone ride in my backseat, so I'll live with it.
