If you’re asking whether works:
A Switch running Atmosphere CFW and an installer like DBI or Tinfoil . Installation: Connect your Switch to your PC or use the SD card. Use the installer to select the 3.0.3 .nsp file. mariokart8deluxeupdate303nsprar work
Because Ver. 3.0.3 was a maintenance patch, many users looking for it are actually interested in the features introduced in the last major version ( ), which added: Music Player If you’re asking whether works: A Switch running
Wait for tool updates: check trusted community tool repositories for updates supporting 3.0.3. mariokart8deluxeupdate303nsprar work
If the game won't launch after installation, delete the update data through your console's settings and try reinstalling the file.