I think you could do one of two reasonable things:
1) Just say no to external radiators! Don't add that 360 external rad, you will ruin the look of your Cosmos 2 when you really don't need that much raddage.
2) Just say no to external radiators! If you're going to build a rig with that many rads, use a CaseLabs case.
Edit: or 3) Just say YES! to external radiators, but do it properly. Get that Phobya 3x3x120mm monstrosity, put it in their rad box, and decorate to your taste.
