We have an Intrepid rack sitting here, an Intrepid rack is a front steer version of a rear steer Cavalier rack. I have mounted several Cavalier racks on these old Mopars before, I don't picture it working on this car at all.
Reasons a Cavalier/Intrepid rack won't work:
1) The 57 frame is way too wide, the Intrepid rack is several inches too short to reach the frame rails, mounting it would be a pita.
2) Because of the location of the torsion bars, a rear steer rack (the car has rear steering) would have to mount below the torsion bars (there is not enough room above them) and that would place the rack below the frame crossmember, and in a dangerous location with absolutely no protection of any kind.
3) Because the rack would have to be mounted so low, and behind the sump of the oil pan, the rack would have to be mounted so the steering column connection would face straight up for the steering to enter the car interior at the firewall. That would place the rack at a 90 degree rotation from how it would normally be mounted. I wouldn't have an issue mounting the rack at some rotation from normal, but 90 degrees is a stretch in my mind. Keep in mind, the rack is still hanging out in nowhere land, and we don't know what issues the exhaust might also add to the equation.

That brings us to converting the car from a rear steer to a front steer. Without actually dissembling the parts, it appears possible to swap the steering arms side to side and bend them for proper Ackerman, and convert to front steer. Of course, we have not yet mounted the disc brake calipers or rotors, the car currently has brake drums with no backing plates and tires bolted to the drums, there is a lot of room for steering arms to move around. That might all change with the addition of functioning brakes.

Assuming (I'm growing to really dislike that word) the brake deal should somehow work out with the steering arm swap, will that infamous Intrepid rack work on the front? Well, the frame in front of the crossmember is closer together then it is behind the crossmember, the rack might actually be able to be mounted, except for the steering wheel connection. With the rack centered in the car, the steering wheel connection is nearly perfectly lined up with the frame rail.

We also have a mounting height concern with mounting a front steer rack, we have to be able to miss the lower control arm struts. The rack almost has to mount above the struts, below them places the rack down in the danger zone.

If I offset the rack 3" towards the passenger side, the steering column connection is now centered, height wise, at the center of the crossmember. I suppose we could cut a hole through the crossmember to run the steering shaft through, and enclose it with a piece of round tubing. Hopefully it would clear the starter. there might be an issue with the passenger side tire making contact with the end of the rack on a tight turn. Mounting the rack in this position would require some custom brackets, the rack isn't long enough to shift to either side without making brackets to do so.

If I offset the rack 4" towards the driver side, the steering wheel connection would sit just outside the frame rail. The steering shaft would have to pass between the lower control arm and the frame bumper stop, inside the lower shock mount on the control arm. My concern here is that if the suspension bottoms out, the steering shaft might get pinched between the control arm, shock, and the frame. Not something that even remotely sounds good to me. There is also the issue of the driver side front wheel making contact with the end of the rack when turned sharply.

At this point, the biggest concerns are we really don't know how much room we have between the motor and anything else, weather or not the transmission or the exhaust is going to be an issue, and what incite functioning brakes might bring concerning the steering arms and converting to front steer.

I thought maybe someone has converted a 60s/early 70s Mopar to rack & pinion steering, and there may be answers to questions I haven't even thought of yet. Gene