Update (04-29-2017) - Upon request I have added a mirrored STL of the original part. Body-mirroring isn't available in Fusion360 so I did the mirroring with Sketchup which is why the mirrored STL is so much larger in file size than the original.
Version 2 Upgrades:
-Mounting arm radius is smaller; snaps to E3D-v6 cooling fins better
-Added non-slip notches to mounting arms; won't slide down onto hotend during prints
-Both fans angled up to prevent the bed and part cooling prematurely
-Material cooling duct better directed towards nozzle and material extrusion area
-M3 lock-nut mounts added; no longer thread mounting bolts into plastic
Previous Version 1 - http://www.thingiverse.com/thing:2191664
Thanks to ElmoC (http://www.thingiverse.com/ElmoC) for getting me to correct the orientation of the STL for print.
The MakerFarm Prusa i3v comes with a 40mm cooling fan and the E3D-v6 comes with a 30mm fan, so why not use both? This duct uses the 30mm fan to keep the hotend cool and the 40mm fan to cool the material!
Rotate the part so the mounting arm is not at an angle, the layers should be uniform vertical in the z-axis. Use ABS. PLA will be too brittle and will likely break when you snap this piece onto the E3D-v6's cooling fins.
This part has a lot of small details which may be difficult for some printers. I printed mine on a Zortrax M200 with 25 degree support material and heavy infill.