Anyone remember these vintage traction bars ?

No rubber baby buggy bumper on those. They clamp to the front of the leaf. They may help traction on a Mopar but probably not much. Mopar's have a great design of leaf spring where the forward leave are much shorter nd more stiff so they act like a traction bar.
And we like our pinion snuber, no mopar of mine will ever have a set on it.