that would be pretty cool wouldn't it.
but alas, I have never come across such a thing and the one shop that did have a couple of seats, it didn't do any good since they didn't have rails and weren't mounted in the car... the seat might be awesome in one car, with one set up and then totally blow balls in another. only way I found to test out seats was either buddies or at decent car meets if the owners were cool with it.