Is there any guideline for how much you can change your torsion height setting before it starts to screw up the alignment? I want to drop The MoPig's front end a bit more and need to keep this in mind.

It will effect toe, these cars have bumpsteer. Lowering it in the front will also effect caster some to. If you lowered the entire car the same caster would be minimally effected.

That would depend if you have already checked
your toe curve.. if its still stock then any
movement will change the toe in.. you have
seen some of the wheelies that shows how bad
the toe changes

Easy, just measure the toe across the front with a tape. At this point we are not taking an actual toe reading, just looking for change. Measure you current height so you can go back. Adjust you bars and recheck your tape reading. The toe difference will be half the change between the before and after readings on the tape. Generally doesn't change to much. Note that you should jounce the car a few times and roll it back then forward before taking either height or toe readings. Moving either torsion bar will affect the opposite side height as well.
Doug

Here's how it works with me: I drive the car to the local tire shop and say "Hi, I have a 1973 Dodge Challenger that needs to have the front end aligned. How much, and when will it be ready to pick up?"

To pay $70-$80 or what ever it is for just a
toe change is a lot of coin.. I do my whole
front end alignment in my shop.. I paid one
time on the race car.. they turned one heim
a half a turn.. but they did check the front
and rear tires for square in the chassis...
that was fine also... if you do change your
toe.. make sure the steering wheel is straight

Are you lowering because you removed weight from the front? Like removing AC system? Then you are putting it back to where it was. Most likely OK.

If you are lowering just to alter height then camber will chase after a 3-4 turns. If you like your front tires then get it aligned.

Camber change is the biggest problem that will wear your tires pretty quickly. Toe can be reset with a tape measure and a helper.

Since we don't know your TB rates, and not sure of your use, a rule thumb for me, if using any tire package really wider then OEM, is anything that changes the ride height by adding more then one passenger, that is also assuming you have your alignment set with driver weight ballast properly located. #1 rule by others smarter then me, "everything effects everything else"

For how long the car has been down and the power you are making I'd check it anyway. Buy a Longacre caster/camber gauge and some 14 ga. steel sheets so you can fix it yourself instead of wasting half the day going to a tire store. Usually the kids running the alignment rack can't get the steering wheel straight if their life depended on it.

Agree with jerimiah, I have a gauge and do my own alignments, bought a modern tire machine and digital balancer, saves time and frustrations in the long run. No more wasted days and money.

Any ride height change from the Factory setting will effect alignment - toe worst, next caster, least camber. Before I started doing my own alignments at home, I would set the ride height where I wanted it ( including the rear end height ) and then take it to an alignment shop and tell them to do the alignment based on the existing ride height. Two suggestions on alignments that are often over looked. Make sure the center link is parallel to the ground. Often after market idler arms can screw this measurement up. It's one thing to have a bump steer problem. It's a hole other thing to have a bump steer problem that aint the same side to side. Try to keep the front tire / wheel offset as close to the OEM package as possible so that the scrub angle (built in to the spindle and not adjustable ) is what the OEM intended. Lastly, (I guess that's 3 things ), after you have set your front end ride height where you want it, take a look at the tie rod angles as compared to the lower control arms. They should parallel each other for minimal bump steer. The farther they are from parallel, the worse the bump steer it gonna be. With lots of front end travel, it is very difficult to satisfy this through the entire range of travel.