How much difference will it make?

Throwing parts at it, especially expensive shocks is the wrong approach with what you have and what you’re trying to do. If it were me...

1) Remove the rear clamps on the leafs
2) Unhook/remove the front sway bar
3) Run it
3a) Lose the Nittos and replace with MT or M&H drag radials

MANY a mopar has hooked and went fast with SS springs and the basic of shocks. I also think that at your power level, loose (90/10) shocks and slant 6 t bars will do wonders.