Leaf spring re-arching.

When I was younger cheaper and full of energy... I took a set of SS springs rigged
them up between two trees and used a bottle jack and pressed them backwards against there arch. I did de arch them and even them out so the car sat lower and
level. Don't know if this DANGEROUS method would work to put more arch in (metallergy). Anyway springs still in my Valiant and still level and no sag (20 years)