The installation process is the same as it was for the Vantec AeroFlow FX 92 we just reviewed, encountering the same problems with the annoying LGA 775 pushpin design. An upside to the matter is the clearly written and easy to understand instructions for the three different bracket installations.
First you need to make sure that you apply your thermal grease to your CPU. Like I mentioned on the FX 92, the thermal grease provided is very easy to apply and you only need the slightest drop of grease. You won't need to use the whole tube provided. You could probably get 5 or 6 installations out of the thermal grease provided.
The next step is to install the correct bracket mounting device to the CPU Cooler base. In our case we had to use the LGA 775 pushpin design. It's quite easy to install to the brackets to the base because of two simple screws. The hard part is actually attaching it to the motherboard.
Before installing you need to make sure the arrows on the four clips are pointed towards the device and that the clips themselves are not pressed down. For more detailed instructions on the whole process please refer to this guide over at Hardware Zone. Be aware that the included instructions on the User's Guide are wrong for the installation of Step 5 in that you don't need to `tighten' the lock after placing it in the motherboard, but rather before installation with the arrows pointing towards the heatsink.
I also found it difficult to push in the two clips underneath the 120mm fan because there is hardly enough room to place a finger under to apply pressure to install the pushpin.
During the installation I noticed that the CPU Cooler came pretty close to hitting my case. I have the NZXT, a top motherboard mounted case, so if you have a similar case you may want to double check the specs to make sure it fits in your case. I also found that the heatsink was very tall and would almost hit the side panel of the case. You may also want to check and make sure that the heatsink doesn't hit the side panel of your case if you had either a fan or some other part in the way.
Here's how it looks whenever everything is back together inside of the case.