OK, I may be new to eagles, but I'm an old hand at lifting, and here is the point were you have to ask your self what am I gonna use it for? If you go Wheeling every weekend, or keep it as a hobby car it might be worth it, but if it spends the majority of its time on pavement you'll likely wind up with some lift regret. I see the cheapest way to be the spacers in the front and shackles or blocks in the rear. However given that the CV shafts have a fairly extreme angle in the stock position I'm imagining your gonna go through CV joints like crazy. if you want to keep the independent front end. You could do one of 2 things.
You could leave the diff housing were it is, pull both control arms, and fabricate a pre-runner style suspension. if your not familiar this involves lengthening the control arms, and using a longer spring. basically the idea is that you wind up with a less extreme angel on the CV shaft. Obviously if your not a master fabricator its probably way out of the question seeing that it involves building completely new control arms and getting the CV shafts lengthened along with a long list of steering mods.
The easier method is to fab a drop for the front diff housing. You would then have to take the entire front suspension and at all the mounting points make some sort of spacers or brackets to drop the whole suspension equally you could then use longer springs to raise it up, and get the CV shafts to a point were they would be at a reasonable angle. Then the rear is pretty straight forward, you could get new spring packs or use add-a-leafs or blocks or shackles things to watch in the rear are drive shaft angle and length it I'm not sure how much travel is in the slider, but if your bottoming out you could destroy your rear or your t-case, ask me how I know that.
The logical way, and probably the way I'd do it is get a d30 from a Cherokee, and do a solid Axel swap, alot of fabrication, and alot of builder parts from Rusty's, but your lift is only limited by your drive shaft angels, and your imagination. plus then you can eliminate that air actuator on the front Axel. Ive seen threads on this swap, they all involve a massive amount of fabrication, and I wouldn't recommend welding to the uni-body (just a general bit of advice)