[Richard]

Not sure what the focus on spring width is about? Many factors determine the actual behavior of the spring. Width, length of pack, number of leafs, thickness of leafs and arch of pack. All off the shelf lift springs and stock replacement type will ride and behave like stock springs. FIRM. If you want a nice spring contact Alcan, Atlas or Deaver. The Deaver springs in the rear of my 72 have almost 16" of travel, 10 leafs and are very compliant. While my rear springs are custom length they could be made to stock length as well.