I think everyone who has responded is reacting to the information itself which might not be accurate, what I mean is that when I was doing the alignment on my Challenger, I had several instances of setting the alignment then pulling out only to have the passenger tire "collapse" the camber meaning that the top of the tire was leaning dramatically inwards toward the center of the car. This looks like the tire is now "up and inside" the fender; if this happens on both sides, it would look somewhat like the ride height is being altered or failing (kind of is, but has nothing to do with the torsion bars).
What causes this is the upper control arms moving in their adjustment slots (usually the front, but could be both). This is a result of 1 of 2 things, first is an improper alignment which is placing significant stress on the UCA's and pulling them, and/or the adjustment bolts not tightened correctly or sufficiently. In my case it was a combination of things but everything stemmed from the toe adjustment being way too far out putting a significant amount of force onto the UCAs.
Normally someone doing alignment would set caster, then camber then toe last. What I found is that with these cars (vintage Mopars) is that if using stock or factory parts the following,
Caster isn't really adjustable to a large degree, rotate the rear UCA adjustment all the way out and that's as good as it gets.
Camber can be adjusted slightly. most say turn the adjustments all the way in and you are close
Toe can be set to 1/16" in
Well, I can say for sure that in my case, I needed to set the Toe very close, then go back and check the Camber leaving the Castor (rear UCA bolts alone) before attempting to move the vehicle. I had to learn this the hard way and had to mess with it many times before I figured out that while the Toe was relatively close (or so I thought), in realty the passenger side was pointing out and trying to go a different direction than the drivers side. I ended up spending some quality time ensuring that both wheels were pointed in the same direction, then sent the actual Toe, then went back and checked the camber, then locked EVERYTHING down.
One last part and I will get off the box... if you rebuilt the front end using a "kit" from someone like PST (nothing really against them) you might be using poor quality UCA adjustment bolts. The ones you get in many kits have the flat for the eccentric washer machined all the way to the bolt head (effectively removing 1/3rd or so off the bolt) whereas the originals were only machined on the threaded end leaving the body of the bolt round and intact. I mention this because the aftermarket bolts tend to "lose grip" and can allow the UCA to move. I ended up sourcing some high quality Dorman UCA bolts to combat this; this is absolutely and issue if the Toe is off when the shop/technicians attempts to test drive; it will cause the UCAs to move and the Camber to move dramatically resulting in the tires leaning in (or maybe out, but in would seem like a ride height issue).
In short, it might not be a ride height issue at all but something else. Bottom line is that the shop you are using may not be experienced or understand old Mopar suspensions...
Sorry for the rant, hope something here is helpful to someone.