Configurable spool holder for the German RepRap Neo

The customizable spool holder of peka (which in turn was based on the one from Luchador) had a too small gap to fit the wall of my RepRap Neo, when printed with Simplify3D.

So this spool holder has a second configurable parameter, the gap.

Instructions

The attached STL is for a length of 80mm and a gap size of 2.8mm which turns out to be a gap of 2.4mm when printed using Simplify3D and two shells.
For different lengths and gap sizes, use the OpenSCAD file.