I designed this Mount because I got Heat creeps with the normal Coldend. Because I already have a water cooling system for my HEVO I tought I could use it to cool the Chimera Aqua. After I upgraded to the new Coldend and connected it to my system I never got Heat Creeps again - not even with PLA and a Full Metal Throat.
I use 3 120mm Fans with a 19 Watt Pump. It is complete overkill but I need it to cool 2 printers. If you want to cool only the Hotend, 1 120mm fan with a little pump should be more than enough. But don't forget the LED Fan, it will cool way better ;P.
Feel free to ask your questions in the comments. I do NOT provide the Step file in the File section because of bad experiences. If you ask nice I will maybe give you the Step (pretty sure if you are not commercial) ;D
The screw hole on the left side is to trigger the endstop. It is necessary because the mount is too big and the carriage can't trigger the endstop so I needed a "workaround".
I hope you will have fun with your A10M or A20M without the crappy stock Hotend ^^