Trunk lid not opening far enough - 65 Dart

The trunk lid on my Dart doesn't open very much on it's own (pic 1 below) when I unlock and let is go. When I push it up it comes down pretty far (pic 2 below). It goes up easily when I push it up so I know there isn't anything binding it. My guess is the torsion bars are weak. Can they be re-torqued? Do you know where to get NOS or reproduction? Thanks

Trunk1.jpg Trunk2.jpg