Hy, I'm a French Maker and we are basically in the same situation, i'm trying to mount the E3DV6 on my Ultimaker. I don't have changed the firmware but directly bought a new Motherboard from Create it Real which is way smarter (and is compatible with SLA for my next printer ). Do you still have the .stl file of the mount ? Because i have made a diy montage with the original Head support, but it's pretty heavy and ugly to be honest. I'm trying to make my Ultimaker as fast as possible. I have also deported the fan out of the Head and there is now 4 big 12v fans on the frame of the machine, It work pretty well, i have still a really good quality.