Support for J-head on Printrbot Simple Metal

I recently upgraded to the latest Alu Extruder V2 http://printrbot.com/shop/printrbot-alu-extruder-v2/ and found that my E3D and J-head hotends did not sit as securely as I liked.
So I created this shim to place below the mount.
It goes onto the neck of the hotend where it would be supported on other printer. The hotend is then inserted through the frame into the extruder and the shim, hotend and all is attached to the extruder with 3 3mm screws. This roughly holds the hotend in place while y