In August of 2003 I converted a dual P3 1Ghz workstation to water-cooling to reduce noise in my office. I purchased Innovatek components from SharkaCorp out of California. The follow is a photo-pictoral of the build process over the course of a day. Click on the pictures to see a larger version (in a separate window).

The mis-en-plas of a water cooling installation. All the components needed to convert the system to water cooling. The parts, in a vaguely clockwise spiral: a 120mm fan (ultimately replaced with an ultra-quiet Vantec Stealth 120), cooling solution (actually isopropanol), an Eheim 1046 pump (with 12 volt molex connector), a 120mm radiator, two Socket 370 (Pentium 3) cooling blocks, a cooling block for a GeForce 4, a cooling block for a Northbridge chip, a plug-on reservoir with right-angle adapter, two Y-splitters and a flow meter. Various other fittings, 8mm hose and heat conductive goop are essential.
Opening the existing system up. This machine is mounted in a 4U rackmount case with a nice bit of sound-proofing. I have three of these cases and can't find any more of them. What's great about these cases is that they are not welded anywhere - the enitre thing is held together with screws. So you can disassemble it in more ways than you can imagine, top, bottom, sides, everything can come off. At this point the top, front crossbrace and drive caddy has been pulled, but little else is done.
All cables are out, the CPU fans and Northbridge heat sink are pulled. The chips have all been de-gooped in preparation for the cooling blocks being installed. The GeForce 4 video card is out, too. Everything is being test-fitted to make sure there's enough room for all the bits. You can see that I'm test fitting the radiator and fan at the front of the case, with the pump and reservoir right behind it. The connector coming out of the top of the pump is the output, the right-angle fitting on the reservoir (essential to fit in the tight confines of this case) runs to the bottom of the reservoir.
Ripping the massive heat sink off the GeForce 4 video card. You can see five patches of heat conductive goop - for the GPU and four RAM chips. After cleaning, I would install a water cooling block on the GPU and use heat conductive epoxy to glue some Tweakmonster Ramsinks in place.
Cooling blocks are installed on the two CPUs, Northbridge chip and video card. Now the fun really starts! It was at this moment that I remember the hard drive cooling block which fits around a 3.5 hard drive and still fits in a 5.25 bay.
The emotionally rewarding experience of pouring water into your computer. Actually, its a mixture of three parts distilled water to one part of Innovatek cooling solution (which I believe is isopropanol). Everything is still turned off at this point, just letting the reservoir, radiator and hoses fill up with fluid...
DISASTER! The fluid starts leaking out the hard drive water block, right onto the hard drive. One of the seals on the clear plastic rod running between the two halves of the hard drive block is ruined. Off to Home Depot to buy some Type 1 Silicon Rubber. Note - you always want to use type 1 silicon in a situation like this with unknown materials. This is the same stuff you use on aquariums because its non-toxic. It smells like vinegar because it has acetic acid in it. Using Type 2 silicon could lead to plastic bits melting from the solvents, etc.
While I was at Home Depot, I bought some mounting hardware for the vent-fan-radiator assembly, using rubber bushings washers and all sorts of good stuff. It was pure good fortune that this case happens to have a 120mm fan mount in it, making it darn easy to bolt the whole thing together. You may be able to see that across the top of the radiator I had to cut off some mounting brackets to get the radiator to fit in the case. The radiator essentially floats in the case, bolted to the fan, which is in turn bolted to the 120mm vent on the case. The wires in the shot are the power & hard drive LEDs, plus the power and reset switches.
Getting back to the task at hand, this is my thoroughly siliconed seal. Water leaking inside a computer is bad. On a related note, this was the only time I had a hard drive block leak out of the half dozen or so I have installed - the rubber seals inside the blocks are a bit loose, you have to be very careful inserting the plastic tube into them. Apparently in this case I was not careful enough.
Back to work! The pump is actually running in this shot, cycling water through the entire system. An astute observer may notice that the motherboard power is not plugged in - I'm using a bypass plug connected to the motherboard plug to allow the power supply to turn on and run the pump without heating up the motherboard. The water loop is as follows: out of the pump, into a Y connector, each side of the Y goes to a CPU block. The hose out of CPU 1 goes to the video card, the hose out of CPU 2 goes to the Northbridge chip. Then another Y joins together the output of the Northbridge with the output of the video card, and then it goes on to the hard drive. The output of the hard drive goes to the flow meter, then into the top of the radiator. The output of the radiator at the bottom goes into the reservoir, which is mounted to the pump. The radiator-reservoir-pump sequence is important, since it allows air to collect at the top of the radiator and reservoir, rather than continue to be cycled in the lines.
Buttoning the system back up again. I skipped over the challenge of getting a water cooled hard drive back into its caddy - just be aware that when your hard drive is trapped by short water hoses, its tough to get it mounted into anything. Lots of hoses running back and forth in this machine, but very little air flow, and virtually no noise... the only fans left are the 120mm at the radiator and the Enermax power supply whisper fans.