1971 Dart Swinger Worm Gear Adjustment

So you've already got some "new" parts on there?
All the ball joints?
Just replace the rubber stuff then if you haven't already.
I mean you are going to have to take the LCAs off anyway, right?
The only caveat there is are they good parts that someone put on there?
Do a search on here and I think you will find people complaining about premature failure of junknees ball joints.
If it were me and I was having to take the LCAs off and there was any doubt I'd put some MOOG on there.
You mention coil over?
I"m the wrong person for that.
In the first place, I'll call you a heretic.
Seriously, I really don't think there is any overriding reason to do away with a torsion bar suspension. (Pun intended)
It was light years ahead of it's time and there is nothing more surefooted.
Especially with the factory sway bar.
(I mean, why not get a Mustang with cracked shock towers.)
Now, if someone is building a Hemi Dart and the want to close the hood without cutting a hole in it that might be another thing. (Been done)
A coil over with rack and pinion might be necessary to drop the engine.

You probably haven't seen this.
A torsion bar car.
Just like the T/A and AAR.

One Lap of America in a Plymouth Valiant