This is a two piece mount design for an E3D-V6 for a CR-10 (or CR-10s). The large mount secures to the existing top two screw heads on the hotend bracket. The smaller piece secures itself to the the larger piece by using 2x 20mm M2.5 machine screws with small hex standoff nuts trapped inside the larger piece (the hex standoff nuts could be omitted if larger 3mm screws are used). This bracket design chokes the top of the E3D heatsink and holds the entire E3D so that the tip of the hotend is nearly identical to the stock setup, requiring minimal adjustment once set up.
The small piece offers an anchoring location to zip-tie the hotend's wires securely. The large piece also offers a zip-tie anchor if you use my E3D heatsink cooling fan mount (can be found thru my profile).