Thanks to MattEllison for a great idea, no screws, nuts or bolts just using the existing reel holder to secure it, I printed and used Matt's original and it was great until I put the reel up around the other way, hmm needed one on the other side as well and being just a little shorter is good for me, these guides also stop the possible reel tangle after a retract flies loose. I made sure it's secured with a tiny blob of hot melt glue on the right and left edges.
I made this by cut & shut in Orca Slicer!

Important update: I found an issue with this, if you print a model that asks the extruder to travel from one side of the bed to the other and you're using a full spool it could unhook a full loop of filament off the spool, causing a tangle, I'll think of something better, sorry.

Print Settings
Printer brand:
Creality

Printer:
Ender V3 SE

Rafts:
Doesn't Matter
Supports:
Doesn't Matter
Resolution:
.2mm

Infill:
20%

Note: If you can’t fit the guide over your spool holder, just file it a bit. The fitting should be tight but should not look like it is stressed or “bulging”. Make sure you are extruding enough as the stock settings can be quite off from the factory.