You'll need the shaved CVs, and possibly custom driveshafts, or you will be in real trouble from everything I've read. Basically, it seems that once you go and exceed the specs of the OME fitted with a top spacer (whether Boiler or JbA) and maybe a clevis lift, then you really are into serious cash. I wouldn't personally go there, I suspect it costs more than you gain - unless you really want a "I wonder if...." project.
If you really need a lot more ground clearance than the KJ can give (with the usual mods) then really you ought to be looking at a different vehicle - just my view (and you might reasonably ask - what do I know!)
From my past experience of modding bikes (many years ago), it very easily gets to the point where you are spending large amounts of cash and time to do mods; more cash to correct the problems that the mods throw up, and then more cash still to "tidy it all up". You eventually get to the point where you realize (too bl**dy late) that it would have been a fair bit cheaper to have bought a different bike with the specs and capabilities that you wanted. Do NOT ask me how I learned this.
