I literally JUST installed mine and am posting about it now.
I used a little different method - ie., the one that Mikee recommended in another thread here:
[*]Tilt the unit and slip the one side of the clip into it's retainer tab
[*]Level and center the unit over the CPU
[*]Slip a small to medium-sized flat head screwdriver down between the fan blades and heat sink fins until you reach the clip bar (I turned the screwdriver perpendicular)
[*]While holding the HS/fan unit steady with the palm of one hand, push down on the bar with the screw driver until the clip is within reach of its retainer tab
[*]With a finger from the hand holding the unit steady, push the clip the final way onto its retainer tab.
Amazing. It took under 30 seconds - which including steadying and centering the unit and trying to get the clip down where I needed it to be a few times.