Well I made a mod to put that song in of course.
Honestly I made it to get my mind to stop wandering towards it in the middle of a race, but after testing it, it fits way too well to not share it with the world.
Install Instructions for CEmu (In case this is the first mod you're installing):1. Create a folder in CEmu's "graphicPacks" folder for your mods.
2. Drag and Drop the content folder in the zip file into that new folder
3. If you don't have a rules.txt file, make one with these contents
[Definition]and save that file at the root of the graphic pack folder you made with the "content" folder NOT IN THE CONTENT FOLDER that is important.
titleIds = 000500001010ED00, 000500001010EC00, 000500001010EB00
name = Installed Mods Toggle
path = "Mario Kart 8/Mods/Custom Installed Mods"
description = This applies all the mods installed in the mod folder to the game
version = 3 fsPriority = 100
4. (If CEmu was open, close and reopen. CEmu only scans for Graphic Packs at startup.) Check your Graphic Packs window, you should see an option called "Custom Installed Mods" inside of the mods section of Mario Kart 8.
5. Check the box next to it, and start the game.
If all went well, next time you load up Bowser's Castle you should hear Asteroid Coaster from Sonic Colors instead