I have a 78 CJ-5 golden eagle. I just got it last week with the 304 and a 6" lift on it. The issue that I am having is if I back off the throttle and then jump back on it, it feels like the rear end is twisting sideways. I thought that It might have a lockrite in it as mine used to do this in my XJ just not as bad.
Lift loads on different sides during acceleration/deceleration.
Probably an open diff since the movement is dramatic.
Remember, engine torque unloads the right rear when you accelerate, and plants the right rear when you decelerate.
(One wheel wonder peel in open diff vehicle with enough power to spin one wheel)
Soggy urithane bushings will cause the diff/springs to move around quite a bit under the vehicle magnifying the 'Issue'.
The extra length in the lift springs will allow the springs to flex more as you Load/Unload the rear end...
And if your frame bushings are shot, or been changed over to soggy urithane, that will further magnify the problem.
IF you street drive the vehicle, and you want to stop a bunch of this crap...
Knock out the urithane bushings that allow for large deflection angles,
And press in some stock, hard rubber bushings in frame and springs.
Get rid of 'Lift Shackles'! Those kill your steering geometry and magnify deflection.
Go back with stock height shackles, and weld in supports between the side pieces to keep them from further deflecting. You are looking for 'll' shackles, not '//' or '\\' shackles.
Using a soft but resilient engine and transmission mount will take much of the engine torque issue out of the situation,
And DO NOT forget the torque arm on the transmission/transfer case mount!