The Mercedes rack is a pretty good rack. I was thinking the same thing about rear steer as i think you will be getting in trouble trying to mount the idler arm and box .Plus the frames usally step up in the back makin it hard to put castor in the spindles with the steering arms .The other thing you could look at would be spindles that had unboltin steering arms,that way you could fab your own steering arms.With the rack that would be a plus cause you could slow the steering down by makin longer arms(within reason) and correct any bump steer.It would also have to take in account were the motor goes as the oil pan allways seems to be in the way with a rear steer deal.
