I realize you asked over two years ago, but for what it's worth... I managed to remove the two lower EGR pipe nuts with only WD40 and a 12mm ratchet wrench.
Also, I confirm that it is possible to remove the EGR pipe and put it (or a new one) back in without disassembling anything, as clasey explains in post 1. As long as your hands are not too large, that is. There is a lot of cursing involved.