How to Control E3D dual extruder fan speeds

I bought the dual tool head E3D upgrade kit and have begun to install it on my ~2015 gMax 1.5+ XL. But the only documentation available for this upgrade kit is the Dual E3D Extruder Installation Guide, which doesn’t say much at all. Questions that I need answers to...

* With the upgrade in place there are now 3 fans instead of just one. How are the extruder-specific fans to be powered and controlled?

* Most of the picture in the Dual E3D Extruder Installation Guide are actually of a single extruder tool head. Can we get some pictures clearly showing the proper wire management for a dual head?

* Any chance of filling in the existing Guide with enough step-by-step instructions to justify calling it an Installation Guide?


- Bob