Not too sure; I think R34 GTT rails were different to the rest? Anyone else wanna help me out here?
The seats themselves are the main difference in height, they're a lot smaller in the base than the massive pillow of GTST seats. Having said that though, they are a little harder, so I don't know how you'd go with your back injury, but the majority of "hard ride" in my car is due to coilovers, so that'd come back to your suspension.
If they're the same rails though, if you're at an event I've got the liner at, I'm happy to do a quick in/out for you to see how the 32 seats sit in your car... Just need confirmation it fits heh