[ImperialCrown]

If the 'clunk/pop' noise is in the front as you turn in, that is probably your worn part making that noise.
If the excessive steering play is there with the vehicle at a stand-still, then the wear has to be in the front.
If the vehicle has to be going down the road for the major steering play, then it could be in the rear suspension.
With the weight of the vehicle on all four wheels and on a level surface, have a helper turn the steering wheel right and left while you are under the front looking for slop in a steering or suspension component. Sometimes it helps to put your hand on a joint to feel the play if you aren't sure of what you are seeing.
The front track bar b/j and upper and lower b/j's were common wear items. The track bar has a b/j where it mounts to the left frame rail. The right side of the bar attaches to the front axle housing.
Have the helper then push on the rear 1/4 panel to rock the vehicle to the right and left while you look under the rear at the triangular control arm at the top of the differential. The rear b/j is possibly worn as rubber mounting arm bushings could also be worn.
Hopefully you will see the worn part movement where there shouldn't be any.

 

[browens1534]

The steering gear box seems to be a weak spot on these...

 

[dana44]

Bushings are designed to be the wear parts instead of the hard parts (A arms, control arms, things like that), and they can cause wandering. Agree with how to check everything. How is the wear of the tires? On the front it can help identify bushings, the rear can also be a visual of shiny metal spots where things are sliding against each other, meaning a slop location but tires on the rears don't show wear the way the front can. Steering wheel at a stop and not running should be about 1.5 inches back and forth tops before feeling resistance. I had an old 76 Honda (yuk) that had a front wheel bearing that was worn and the front wheel would actually move in and out almost half an inch driving down the road. Luckily it stayed together from Virginia to Washington state, but grooves, yeah, jumping side to side was what kept me awake that 74 hours.

 

[95groundpounder]

Haven't driven the Jeep much and honestly haven't looked for the items mentioned above, but lately I have looked at it in our parking lot, (which is near level) and noticed that compared to other jeeps of the same generation it seems to sit quite a bit lower (looking at distance between top of wheels and wheel openings). Would sagging coil springs cause wandering as well?

I assume they are original equipment and have over 10 yrs and 240k miles on them. Tires are same as size listed on manuf. sticker on door.

Is there a method of measuring whether the springs have sagged any?

I have heard/read other posts where spring lift kits can cause issues with handling, was wondering if the same issue could be here with severe sag?

 

[MoparNorm]

Haven't driven the Jeep much and honestly haven't looked for the items mentioned above, but lately I have looked at it in our parking lot, (which is near level) and noticed that compared to other jeeps of the same generation it seems to sit quite a bit lower (looking at distance between top of wheels and wheel openings). Would sagging coil springs cause wandering as well?

I assume they are original equipment and have over 10 yrs and 240k miles on them. Tires are same as size listed on manuf. sticker on door.

Is there a method of measuring whether the springs have sagged any?

I have heard/read other posts where spring lift kits can cause issues with handling, was wondering if the same issue could be here with severe sag?

Re-read what ImperialCrown wrote. My money would be on the front axle ball joints.
Best way to tell, jack it up so that both front wheels are off of the ground, support it SAFELY on axle stands, and tug at the wheels, side to side and top to bottom, while having someone visually inspect the movement. It's likely not the springs, very likely that "pop" is the source of your problem, either ball joints, tie rod ends, steering arm ends, or steering box.
Eliminate by test, not by part replacement, until you find the suspect area.

 

[95groundpounder]

Now at 262k... had several thousand miles ago replaced the "boomerang" and the ball joint, issue went away instantly.

With it in the air, should the springs in the rear be able to be removed without a spring compressor?

 

[MoparNorm]

Now at 262k... had several thousand miles ago replaced the "boomerang" and the ball joint, issue went away instantly.

With it in the air, should the springs in the rear be able to be removed without a spring compressor?

Not likely.However removing the shocks and sway bar links might allow that, but still a chore.