This script allows you to rename the final SRS progress level in your WaniKani pages (in case you don’t like the idea of burning turtles…!)
You can type in whatever name you like using the Set Name menu in the Tampermonkey drop-down:
The new name will be substituted in your pages across the site (except in FAQs, forum postings, and the like.)
Ah, just what I needed! 
Any plans on extending this to all SRS levels?
You shouldn’t encourage me 
Yeah, I might do that, if it seems like there’s demand for it.
It seems the script only runs on page load; does this change the SRS popups during reviews?
There’s already a script for that. Not sure what it’s called though. Technically you could modify mine to do that too.
I’m not really using this script, just wondering whether OP remembered them
Ah, no, I forgot about that!
Please do that. I want that!
That could be fun
Level 1: 負け犬
Level 2: 弱弱しい
Level 3: 中級
Level 4: 大丈夫
Level 5: 神
Finally I can murder turtles in whatever way I like!
Level 1: Rebecca Black
Level 2: Nickelback
Level 3: Hall & Oates
Level 4: Beastie Boys
Level 5: Beyoncé
Yes, I will probably steal some of your code if you don’t mind! 
Yeah, I think I’ll look at it this weekend 
Feel free! Just run the new version by me so I can make sure they won’t conflict.
After further experimentation, I think it might be better to take a different approach.
I’ve created a new script to allow renaming of all the levels (the five shown on the dashboard anyway), so if you’re open to it, I would ask that you add support for my script into your script, and then people could install your script as a companion to mine to extend the custom names to the SRS popups.
If I did it all in my script, we’d have duplicate code, and we’d both have to take pains not to step on each other… I think it would be overly complicated.
I have some proposed code changes I could send you if you’d like. I’ve been running it all weekend, and it seems to work well.
Theoretically people shouldn’t use them together.
Feel free to send it to me and I’ll take a look. No promise that I’ll include it with my script though. Right now this is my most popular (and simplest) script, so I have to be really careful.
Yeah, I suppose I could just put your code into my script (with your permission and crediting you of course) and then people would just run one or the other. I don’t know how many people would be interested in my script anyway, although it is kinda fun 
I’m still interested in an all-level-renaming script, if only for fun 