Throwing 4in springs on will cause the pinion angle to be more at an angle. A transfer case drop bracket should be used to lower the angle. I would also use a drop pitman arm to lower the angle of the steering linkage. You can make brackets to lower your track bars or you can get adjustable track bars instead. Also I would upgrade your stock shocks to better ones. You can run stock shocks on a 2in lift but when you go to 4in lift and plan on doing any wheeling you will mess the stock shock up. Also your end links on your sway bar will not work with 4in springs so you can either disconnect the front sway bar or get quick disconnects.

The springs do not qualify as a "lift kit" but will lift your Jeep.