This is the wiring loom I designed some time ago.
I've used it at work as a switchboard technician countless times and have gotten excellent results out of it. The results were so good that my coworkers wanted one too!
The pieces can be zip-tied together around the outside with an 11" zip-tie.
Works with up to 10 AWG wire, but also works great on small wires.
Both pieces can be printed together as a model with multiple parts.
I'd recommend ASA or PETG if you're going to abuse it like I did mine.
I unfortunately don't have any pictures of it in action, only of some wiring I did with it.
The author marked this model as their own original creation.