Will new torsion bars correct that POS, bucket-o-bolts feel I have?

Don't get me wrong, I'm not trying to suggest that everything I've posted is needed to fix the problem at hand. I was trying to answer all the OP's questions, and I may be getting ahead of the immediate issue in doing so. I wouldn't just go out and buy new torsion bars, shocks, strut rods, and frame connectors and throw them at the car.

I would-

Visually inspect the entire suspension for broken and loose parts
Make sure the ride height was where I wanted it and...
Verify the alignment!!!
Have the alignment set up to the specs I posted, if it isn't already

Now, everything is supposedly rebuilt, so there shouldn't be any worn out parts. Shouldn't be. Assuming I didn't find anything weird, I'd have the alignment set to modern specs. I'm guessing it isn't. I'd also just change the shocks. KYBs have a really harsh ride, and that's likely contributing to the issue, if it isn't the issue itself.

After that I would want to drive it and make sure things were improved.

But diagnosing all of this on the internet is always interesting. I've driven old cars my whole life, so it's easier for me to know what's "just old car" handling vs "something is broken". If the OP is used to newer cars, even the stock handling on a '72 barracuda could be frightening.

And it is hard to mix and match suspension parts. Modern alignment specs can be hard to get without offset bushings. If the strut rods aren't cooperating with the new bushings they can cause alignment issues, adjustables might be the way to go. Even around town driving with tired stock torsion bars is less than fun. Suddenly you've bought a lot of parts!