There are two verisons. The first prints in one color and has to be painted or stickered afterwards. The second version (All files with "Multicolor" at the end) Is for people who can print with different colors and doesn't require any post processing after assembly.
(Update)
I discovered a problem with the 3D files, but it is fixed now
Photos for assembly above.
During assembly, pay attention to the orientation of th part, it is important.
The author hasn't provided the model origin yet.