I couldn't test this myself as I don't own a printer, but it should work. Maybe it is of use to someone.
Glue the bracket to the shell, remove the mounts on the thumbstick (the stick doesn't fit the shell without modification anyways) and glue the thumbstick into the bracket. Make sure to apply glue only to the non-moving parts!
2018 08 05 – v3
.F3D, .SAT, .SKP, .STEP & .STL