Stay away from the lift shackles unless the boomerang one inch lift shackles are used. They will prevent the longer shackle from inverting. Never go more than one inch with lift shackles, as mentioned above, it will cause very negative effects to the steering due to the caster changes made.
I recently bought my first YJ and it came with 1 1/4" lift shackles on the front stock rear and 31x10.50's on 15x10 wheels, and it was all over the road when driving above 35mph. I went to a 3/8 thick HD stock length shackles front and rear, and added a main leaf(removing the spring eyes) from my old original 2002 2wd Blazer rear spring packs to the stock front springs and took the next shorter Blazer spring and added them to the rear. It does require grinding/cutting off the length to center the center bolt holes. Lift result= 2.5-3 inches lift. Also installed greasable shackle and main eye bolts and polyurethane bushings throughout the suspension, track bars, Main spring eyes, shackle mounts, etc.
Most will tell you it is a rough ride, but my Jeep had a nice solid feel to it, handles great with very limited sway. Hits bumps in the road no harder than the stock springs did. The cost was $9.00(new center pin bolts) and took about 3 hours of my own labor with basic air tools and a 4" right angle grinder to cut the springs with.
This pic is what it look like with Warrior 1 1/4" lift shackles front and rear w/stock springs and the bottom pic is with the added S10 Blazer leafs and stock length HD shackles.