I wanted to use the stock Prusa spool holder but didn't want it to take up room in the enclosure I built. So I designed an adapter that mounts to the lid of my enclosure.
I also routed a 7 inch by .375 inch slot in my enclosure lid then designed a cover to minimize heat loss through the slot.
I designed the parts with Solidworks 2018. If you'd like the part files PM me.
I printed with 3 perimeters at a .3mm layer height using a .6mm Nozzle. I increased the layer resolution to .15mm for the filleted portion of the slot cover.
The author hasn't provided the model origin yet.