I currently have a non reference 7970 in my Mac Pro. I may soon be exchanging it for a reference 7970. It is powered by cables that are going in through a removed slot cover that is for the PCIe slots. Could I send tubes to watercool the card through the rear PCIe slots where the cables are? My idea is to put the rad, res, and pump outside the case with the tubes going through the case to the GPU.