I have found the best way to secure the clip on that model.
Is to take an old e3 clip (I go through them) and rip the ribbon off. Then put the plastic clip without the ribbon on top of the good clip with the ribbon.
Seat the good clip on the nor good and tape it down.
Put the old clip on top of it and tape it all down good.
Assemble the motherboard on the heat sink and the metal that goes on the other side. Screw down the small screws that hold it together, and the heat sink screws.
I have been getting some good, easy, dumps that way.