I bought the K1 SE last weekend, and I’ve been having a blast printing with it. The back mounted filament spool holder will not work for me set up. I designed and printed a bracket that clamps onto the side-bar/strut.
I’ve tested it on a few prints and it seems to work well. I removed the short piece of tubing that leads to the runout sensor and installed a longer piece that is held by a “tube holder” part. This mounts to the frame using an M3 screw and an unused, tapped hole. You can see it in the picture if you zoom in.
I have put the files on Printables:
https://www.printables.com/model/1152436-creality-k1-se-side-spool-mount