stock rear leaf springs from slant 6 better for drag racing

I am guessing that the Mopar Engineers R&D was built around max power and traction back when they were testing.
Fast forward to today, between tires, track traction compounds and available power, today it is a different game.
There is information to be gleaned from what was done then, but unless one is building a 70's replicar racer, things have changed.
Hang out at the drag strip and talk to the Mopar guys. There's guys running in the low 10's or better with some impressive 60' times using Superstock Springs and drag shocks.