Welcome to the forum.
All KJ CRDs are at least somewhat off road ready although they vary on what related options, such as tow hooks and skids, were factory installed. Any Jeep dealer can print you out a "build sheet" based on your VIN that while detail how your vehicle came from the factory; I've always been able to get that printout for free.
According to the tire chart, that I cannot locate online right now, those tires will need a 2.5" lift although trim and pinch weld work may be enough per arengant. 245/70/16 is as wide as you can go without any extra work.
Read the NOOB guide (
viewtopic.php?f=5&t=54207) and download the FSMs from the included link. Note that the 2005 FSM lacks the pages in section 7 dealing with diesel cooling and the "diagnostic" portions of the manual (2005 diagnostic manuals were separate publications) both of which are included in the 2006 FSM BUT the 2006 FSM lacks legends or keys to most drawings. Hence I find it handy to have copies of both. Note also that some torque and fluid capacity details in the FSM are wrong.
Re the EVIC I don't know. You might PM geordi as he did an after the fact EVIC install.