yea I was not sure of the size or if its metric, can someone answer these questions? id rather not fiddle with it too much without knowing for sure. Thanks!

Hello, I have a few 7970s with aqua blocks, and I am not sure how to remove the top black part, where the barbs go, so that I can then connect the aquacomptuer SLI/Crossfire multi gpu connector. What tool would I need to remove it? Thanks