This is essentially a re-make of https://www.printables.com/model/666609-ender-3-v3-se-ball-joint-filament-guide with a more reliable mounting option.

As mentioned there, I really like the ball joint filament guide, it's fun and effective. The attachment option for the other model wasn't great though, and required me to glue it in place for it to stay on without worry, so I wanted to use something more substantial. That desire is where the inclusion of the 2020 rails in the mounts collection came from. The clip-on rails here are pulled directly from the models there.

Be warned, the fit here with the non-loose mount option is really tight. I had to lightly hammer the two parts together, but that's exactly the kind of fit I was looking for. You can opt for the looser rail option, try tweaking your tolerances, or even scaling the guide model down a bit in your slicer if you would like a looser fit.

For best results, print with the top of the guide down and tree supports on the rail, as shown in the photos. Normal supports will work as well, but they are much harder to remove.