https://gbatemp.net/threads/release-3ds-...ui.396785/
All you have to do with 3DS Rom Tools is select the .3ds rom, press "Extract RomFS" and then "Unpack RomFS".
I'm actually surprised that you already have the .3ds file. I normally have a .cia and need to change it to a .3ds first with a converter or just get the RomFS folder directly on 3DS with Luma 8 and Godmode9.
All you have to do with 3DS Rom Tools is select the .3ds rom, press "Extract RomFS" and then "Unpack RomFS".
I'm actually surprised that you already have the .3ds file. I normally have a .cia and need to change it to a .3ds first with a converter or just get the RomFS folder directly on 3DS with Luma 8 and Godmode9.