Please take a look at the description of the original model: https://www.printables.com/model/636254-filament-spool-holder. There you'll find the required second part I didn't modify.
The scad-file contains my modification and can be applied to the original p1 stl.
The author remixed this model.
I printed the original FSH but it was a bit too tall. This version lowers the height by about 1cm and removes the hexagonal pattern, as it would be destroyed by my approach.