Leaf Spring Suspension-Orientation question

[astroracer]

I am in the process of redesigning the rear rails for Bad Ast with the intention of pinching the front of the leaf springs inboard 1 1/2" per side (rather then running them straight fore and aft). The reason for this is to tighten up road feel and improve response out of a corner. I cannot find any info on optimizing this setup. All of the circle jerk sites are pretty vague and usually generalize the dimension between 1.5 to 3.00" per side.
Any direction or input any of you may have (Katz or Davi Pozzi) would be greatly appreciated.
This requires building the front and rear hangers with a bit of an angle, a little over 1.5 degs. and I need to know that what I am doing is going to work...
Thanks guys.
Mark