Two marbles puzzle (acrylic plate version)

This is a print in place puzzle with two marbles (glass marble, plastic marble, iron marble, ...).
The challenge is to put the 2 marbles on each of the 2 horizontal platforms.

ACCESSORIES
. 2 marbles with a diameter between 16mm and 18mm.
. 2 acrylic plates 150mmx50mmx2mm
. 2 acrylic plates 30mmx50mmx2mm
. 1 acrylic plate 150mmx30mmx2mm

PRINTING
How to insert acrylic plates and marbles :
. Pause the print at a height of 53.60mm
. At the pause (in this order) :

• Insert 2 lateral acrylic plates 150mmx50mm
• Insert 2 lateral acrylic plates 30mmx50mm
• Insert 2 marbles
• Insert top acrylic plate 150mmx30mm
  . Restart printing

An other version without acrylic plates : https://www.thingiverse.com/thing:7009925