The PCB is easily removed from most C286 units bought on AliExpress. This model has tighter clearances than the case in which most C286 units are packaged. This model was tested to fit the C286 circuit board marked “c286q-21k-06”.
I've had the best results printing on its side. I've had trouble on my printer with the auto-generated supports, so an explicit support was added to the file “c286q-21k-06-supported.stl”.
The author marked this model as their own original creation.