The assembly process is quite simple: 1) assembly the extruder itself 2) use four M3 x 15mm bolts to fix the extruder at the holder (three at the back and one above) 3) place the rail in T-slot and place the holder over it. tighten it with a pair of M5 bolts (rectangular nuts are needed) 4) place the support below, insert it to the holder's "arm" and tighten with M5 bolt 5) insert the inductive sensor (we use LJ18A3-8-Z/BX proximity sensor) to its place. for details of wiring and calibration: https://www.youmagine.com/designs/inductive-sensor-holder-for-k8200-3drag 6) enjoy:) Note: when using chymera, we strongly recommend you to put some thermal insulator (like asbestos) between the hotends, otherwise the heat from one affects the thermistor of the other one.