I don´t give you a building construction, my only tip for you is: you have to rotate the last part for closing the cubi ;)
It´s your turn to find the correct way to complete the Cubic. Please show us your result in de comments..
I print it with Geeetech Silk PLA - pay attention! - the toleranzes because of the size are very small, you have to calibrate your filament and nozzle perfectly before printing.