I don't have a picture of one to post, but here is the concept. A traditional Ford front spring is hung on both ends by shackles that are free to move as the car bounces. If you build in the normal 45 degree, or thereabouts, angle to them, they do a pretty good job of keeping the axle from moving from side to side from road forces.

But, especially if you install cross steering where the steering drag link moves from side to side, everytime you turn the wheel you are pushing and pulling the axle sideways. To counteract this, you can either use a panhard bar to limit the movement, or turn the spring into a panhard bar (sort of) by taking one of those moveable shackles and replacing it with a dead perch that won't move. In effect, the spring keeps the axle located because this dead perch is ridged.

Never used one myself, as I have never used cross steering, but I have seen them. Hope this explanation is clear and accurate.


Don


PS: It does nothing to counteract bouncing, just side to side movement.