Since the original author was so kind to include the files, you can also modify this to extrude the end making it longer if you wish. I did another re-mix like this allowing to hold a pair of scissors also, but it makes it a fairly tight fitting area where it is mounted. I've attached a picture of that printed.
The author remixed this model.
This is similar to the same model, but I moved the lower section to the side to make it side-mountable. I also changed the locking tabs to allow for easier removal since the original is a hard lock. The locking edges on this model are fileted. The lower locking edge has a greater filet allowing for it to release easier when lifting out and up from the bottom. The upper is only slightly modified, still giving it a strong hold. This works with an enclosure since it sits just outside the edge as seen in the 3d image.