If you think you'd want it later, then get it the first time (at least for the internal parts of the axles). I'd do the Super 88 kit as the axles it comes with lets you set your wheel bolt pattern to either 4.5x5 or 5.5x5. If you go with a HP44 Front, it will be 5.5x5. This way you can run it at 4.5x5 now while you wheel your 30 front and will be set for later when you swap in the HP44. I'd also get whatever locker and gearing you want from the start. You can always cut off and replace brackets without much trouble, but it becomes much more costly to rework internal parts of your axle. On a different note, Ed runs Superior chromoly axles in his 8.8 with a Clayton 4 link and 33's on his TJ.
With that in mind, if you can afford it I'd go straight to the Clayton 5" Stretch but run it with stock type coil springs vice coil overs. Coil overs are awsome, but I don't feel the gains are worth the cost. Run it with coils, notch your frame to move the upper spring bucket back, and call it good. You might need a limiting strap on it, but you'll still perform great. Problem is the stretch is expensive. The core suspension kit isn't too bad, but when you add in the fuel cell and different corners you need to do it right the price gets up there quick.
You might consider a 4 link rear without a stretch. This will keep your cost a little lower. Later on you could sell the arms and swap them for longer ones to do the stretch. Might be the way to go. Heck, you might get it on there with the 4 link and not even worry about the stretch after that.
