A couple years ago I got a chance to buy a 91 xtracab pu with 64,000 miles. Only problem is the drivers seat. Has the split seat, and my back is not great. So today I bought a pair of buckets from a 4-runner, 95 model mfg Dec 94. Even found blue seats, although the pattern is different, cloth. Well, the passenger seat in my truck is almost perfect. The new drivers seat is a bit worn, and the passenters seat also almost perfect. So was thinking of taking the cushions and covers off the new passengers seat and putting on the new drivers seat, and maybe just reusing the original passengers seat, maybe have to buy a new cover for one or the other, probably couldn't get a cover that matches original? Anyway, kind of long and windy, but has anyone switched the parts around on the seats? The drivers has the adjustable lumbar support, and the bottom the seat level knob.

 

The lumbar support adjustment is in the frame not the seat cushion. The cushions can be swapped back and forth to your heart's content lol. There are four bolts that secure the seat to the frame on either side just remove the plastic seat sides to get access to them. You may need to lift the cloth from the side carefully if you can't see them clearly. They are about 2-3" back from the front and about 2" forward from the back. 12mm heads if I remember right.
The frame depends on the seat cushion part to retain alignment so be prepared for some headaches getting it back together but it is a relatively simple job.
Hope this helped Aviator.