My thoughts were to build a res around the existing HX (with current fan removed) and then have that piped through a XSPC 3x120mm rad - the resoning being that you might get great heat dissipation by doing something like that.

But as I am not as skilled/brave/knowledgeable as these guy in such things, I just sit in awe at the work that has been done so far - the results gained prove the worth - nice job.