Torsion Bar nomenclature

Are you sure about those numbers?

First off, torsion bars should be the same diameter left and right. Second, the number on the driver's side bar should be odd, the passenger side should be even. If they're both odd numbers then you have two driver's side torsion bars, and that's not good. Third, the numbers don't correspond to the diameters. A 447 bar has a diameter of .081, that's actually a drag race bar, smaller even than a /6 bar (.83"). I can't find a reference for a "347" bar, but that doesn't necessarily mean that isn't what you have.