I am new to the newer Jeeps. I have owned a few of the leaf sprung versions (2-5's, and a 7) and recently purchased an 03 Wrangler sport. About a week after purchasing I had to go up 4", and put 33's all around including spare.
I put a 350 chev engine in my 84 CJ 7 and it wasn't nearly as stressfull or frustrating as dealing with my Wrangler.
I installed a Rough Country 4" w/ pitman arm and tc lowering brackets,(took about 14 hours, and I can do a leaf sprung in about 4-6 hrs.) and still had nasty vibrations.
Yesterday, some $1450 later its all gone. Burnsville off road installed an HD SYE (I would think this a must), adjustable upper control arms (again I would think a must), corrected my speedo, and 1 1/2" wheel spacers.
The wheel spacers were installed because I put 33" BFG All Terrain TA's on stock wheels (they fit the rims nicely and look good) but when BOR put it up on the rack, they showed me where the rear upper spring perches were begining to eat a 1" swath around the perimeter of the rear tires.
I did some tearing around your'e forum here before pursueing some of what I had done and while some things were a little intimidating you folks cover a lot of territory, and there is some very good info here.