with this design follow the described order for proper installation.
1. slide both hot ends into the slots
2. snap 1 side of the fan shroud onto the collar just above the top cooling fins.
3. rotate the fan shroud until the second extruder snaps into place.
4. put the clamp over the top of the nozzles to lock them in place.
5. tighten down the ptc connectors all the way and cut the extra plastic flange off of the outside, this is a tight fit and is required to get these to not bind inside the effector plate
6. insert screws through head before installation of the fans because they will block the holes, i use a couple tiny drops of superglue instead of screws to hold the 30mm fans in place.
7. install the nozzles so they are parallel with the Y axis (6 holes in the effector plate this makes offset in firmware easiest).
8. if shimming is required just loosen the two screws on the nozzle that needs adjustment and insert shim between effector plate and clamp.
let me know if any additional info is needed.