They are great fun these things
You dont need much to fit 33's. You might be able to fit them stock or just a small body lift or suspension lift. If i were you i would take advantage of the standard springs- put some extended shackles on and take the sway bar off and thats the most flex your going to get unless you start doing custom setups. Lifted springs improve load carrying ability and excessive swaying on the road but they are a step backwards in terms of suspension travel.
You also want to keep the COG as low as possible with these shortys so the less lift the better!