Originally Posted by
John Kaufmann
It's good that you asked - gives me a chance to correct what I said earlier about it being a couple years ago, which turned out to be another example of my faulty memory. I found the pictures I took at the time - dated July 2016 - a bit more than a couple years.
It looks like I initially intended to separate the seat from back on each chair, swapping the seats but keeping the backs in the same location. Separating the chair frames turned out to be more than I could do with my tools, so I took just the seats from each chair and swapped them, keeping the frames (the basis of each chair) in the same location. Of course that was all I really needed, because the problem was the cushion breakdown on the driver's chair. [Because I was also putting in seat heater elements, some of that already had to be done anyway.] Basically, you get out both chairs, make the swap (helps greatly to have hog ring pliers), and reinstall the chairs.
In addition to looking at the pictures, I went out and examined my van, and think I understand what OP lawrenceco was asking: There are nylon (?) strips sewn into edges of the fabric to clip onto the frame. Along the front lower edge of the seat, it is actually two strips that work together to snap the fabric to the frame along that edge, and repeated movement of the seat fabric wears them off with time, so that they won't stay in place. That problem remained with the old driver's seat, now in the second row, but nobody notices it there.
I checked ToyoDIY, which gives a list of parts. There is no separate p/n for those nylon strips (or even for the fabric), just for the whole seat cover (if you could even get it). By "whole seat cover" I don't mean the whole chair. There are separate part numbers for seat cover and back cover and headrest. [It's instructive to add up costs of all the individually identified chair components: At roughly $500 for each major component -- frame, seat covers, pads, pad covers, headrest -- the total comes to ~$4000/chair.]