The normal tyre size for the KZ is 245/75 R15(or 30 9.5 R15)
You can fit 265/70or75(not exactly sure) R15 (or 31 10.5 R15 without modifications if I'm correct.
This will definetly increase your vehicles height. +- 20mm
This is the first mod I'll do on a 4x4.
If you still need more clearance you can the fit OME, IRonman, TJM, Mikem ETc Etc suspension. This will give you an additional 50mm clearance.
20mm and 50 mm doesn't sound like much but will make a huge difference.
Your vehicle would also be a little heavier on fuel.