The original model was great, but designed for rear mounted spools. I rotated the Y part about 85 degrees to make this side mounted version. I only converted the Y_Splitter_PC4-M10_V2_rw.stl.
Requirements:
3x PC4-M10 pneumatic connector, inner diameter: 4 mm
2x M3 8mm
Not sure why the original directions said 6mm screws. I needed to use 8mm ones to do it. You could probably use the ones your spool mount came with provided your side mounted spool attachment or placement doesn't need them.
You can probably cut the needed 1" or so 4mm PTFE off the end of the printers tube, but I elected to leave it full length and use the tubing that came with the connectors I bought.
I'm pairing it with the https://www.printables.com/model/320139-bambu-x1-side-mounted-spool-holder/
Print it as uploaded with supports to build plate only. Regular ones are likely best. I also suggest a brim. I used the engineering plate since I used PETG.
The author remixed this model.