Just been through the laborious process of switching over both heads to volcanoes. Now I'm stuck. Firstly, there's no guide relating to fitting the volcanoes on the BB. Similar to mounting the standard nozzles, I've got the broadest flat part of the heater block facing forward. It seems quite possible to mount it 90 degrees to that, though this looks like it would present more of the head block to the tornado from the part cooling fans. (Hoping for a yes/no on this setup from @Greg Holloway). This uncertainty is not the main issue though. Secondly, I cannot lower the IR sensor mount as far as the nozzle, as described in printer commissioning. I've lowered it as far as I can, and when running an auto home, the bed just keeps rising after connecting with the nozzle (thanks to @Chase.Wichert for giving me the drill point for the stop button). Until, I can lower the mount or raise the nozzles, I seem to be completely stuck. Will post a picture shortly in case it helps.