3. Put the bendy clips on so that the bottom section fits into the lip of the water jacket and the pins go into the slots on the clips. Use the last 4 nuts to screw the clips down hard onto the jacket, pulling the CPU core against the jacket. You can see now why you used the short-threaded ends on the other side..

..and there you go, all ready to be slapped into your system and merrily cranked. Oh yes, it looks easy and intuitive now you see it, but trust me, when you have a handful of assorted bits of metal and a CPU sitting on the table in front of you, you try a lot of different combinations before hitting the right one. Or maybe it's just me. Anyway.
Gripe #2 about the original kit, if you recall, was that the pressure of the mounting clip and hence the thermal join was too weak. The higher the pressure the better the flow of heat from the CPU to the jacket and hence into the water. Well, Senfu have done a similar thing with this kit as with their P3 mounts from the original kit. By tightening the screws in turn you can make it mount VERY tightly indeed - easily tight enough to bend the Athlon's PCB if you wanted to (probably not a good idea, btw). You also probably want to make sure you are getting even pressure from each corner - it would be easy to leave one loose, which would possibly leave a small air-gap between the jacket and the core. This is something you REALLY want to avoid, as your precious Athlon will easily fry itself if it has no way to get the heat it produces away quickly enough.

So, after all that, how does it perform? Well, this is the first naked Athlon water-jacket mounting system that I've seen, so I've got no comparative figures for you. I can tell you, though, that my 950-cored Athlon750 chugs away quite nicely at 1080MHz @ 1.8v. With the Senfu gear sucking away the heat it sits at about 10C over ambient, so about 32C during testing under full load - not bad considering the quite low flow rate of the Senfu system. This is measured from the back of the CPU core with a thermal probe - remember the Athlon has no internal thermal diode like the P6 core. With the Globalwin VOS-32 monster-cooler on it, it it was reporting over 50C and was very unstable even at 1000MHz. This system has been set up with this water-jacket on it for a good couple of months now and it looks like it will be the gaming rig here for quite some time. BTW, to get a feel for how this machine performs, check out my recent Abit KA7 and Corsair CAS2 PC133 reviews.
In summary - thumbs up to Senfu for producing another nice bit of kit. Very firm mounting, if a little fiddly to set up. Hopefully they will improve their documentation soon, but regardless, if you've got the Senfu gear and are looking to use it on your SlotA CPU, this kit is highly recommended.