Rear sway bar for 1964 plymouth valiant

Well, I was in the right place at the right time and got the whole thing cheap. So I bought it. It's not that I wanted the big one, I wanted one and there it was.
i get you.

keep in mind the basics: a big front bar induces push/understeer, and a big rear bar induces loose/oversteer, then match your "springs" accordingly with an eye toward balance of front and rear rates.

i'm also a proponent of softer spring rates and bigger bars, in that you can achieve some semblance of ride quality and still have decent handling. but that's a whole theory of handling that can devolve into squawking akin to an oil thread on a motorcycle forum.

anyway, a big rear bar isn't necessarily bad but when you have a high spring rate and the inherent design of mopar leafs short, stiff front section combining the two is a recipe for a very tail happy car.