[Khledar]

Firstly, depending on the ramsinks, the waterblock could possibly be added to them. However; rivets are not too difficult to remove, as all that is required is a drill; however a large serving of caution is wise when drilling computer parts, but ideally you'll only be drilling the rivet :P And if you want to put them back on you'll ned new rivets and a rivet gun, but they're not all that hard to come by; you could also use small nuts/bolts, or some other solution.

Secondly on to the custom ram blocks. They would render better results than the pipe due to increased surface area and would probably be better, however if you're running in a loop be sure to make the channel large enuff as not to restrict flow. Also regardign the surface area issue I think, although I've never tried this, it would be possible to make a copper pipe somewhat flat, or squarish possibly by inserting something square and using a hammer, shrug but taking four pieces of copper, to make a simple waterblock would also be a great solution.