My drag racer friends say if it is stock mopar suspension, adjusting the pinion snubber to about 1/2" helps launches, but during city driving it will whack the floor a lot.
I see in your garage is my second favorite car (ebodies first) 71, 72 RR.
I'm running a four link with coilovers. I gotta be honest I wasn't expecting the car to be able to really spin the tires. I know the coilovers are adjustable which makes a huge difference but I need to really start practicing some launches so I can go to the track this spring. My gps speedo from speedhut has a 0-60 and 1/4mile timer, Out of two tries with the new tires the best so far 0-60 is 5.4seconds.
That's my brothers 71 in the garage, it's next on the list. Funny how side by side they are very close in size.