Assembly:

The assembly contains 3 parts. Base body with holder + 2x cover with figurines.

LED diodes are inserted into the body through the holes. The LEDs are then covered from the front with caps. 

Printing:

Base: 0.4mm nozzle, 0.3mm layer, 10% infill.
caps: 0.4mm nozzle, First layer 0.1mm (translucent part), rest 0.25mm. Full infill.

The first layer of covers is 0.1mm thin, so light shines through it.