The thing that would really complete this mod is to sub out Mario for Twilight Sparkle (admittedly, a trickier task than textures.) Then, someone should get on making me a ponified Luigi's Mansion starring Fluttershy. Pretty please?
The description of the trailer above links to a video with full instructions for adding texture packs to Nintendo 64 ROMs. In case you wanted an abbreviated version, I've copied the gist of it below:
1. Make sure you have a working Super Mario 64 ROM running on the Project 64
emulator. If you've never used an emulator to play games before, make sure you have this working first.
2. Download and install Rice's Video Plugin
. When it asks you to choose install location, make sure to give it the directory in which you've put Project64.exe. (Something like C:\foo\stuff\Project 64).
3. Open Project 64, go to Options>Settings>Plugins and select "Mudlord's Rice Video Build 6.1.4" as your Video plugin.
4. In Project 64, go to Options>Configure Graphics Plugins>Texture Enhancement and make sure "load hi-res textures if available" is checked.
5. Download the Texture pack and copy the folder "hires_texture" into "Project 64/Plugin.