After performing a successful connection test on a 4.3U console, this message pops up after agreeing to perform a system update (details in comments) : r/WiiHacks
MODIFICA WII - TUTTE LE VERSIONI
LetterBomb – Dê nova vida à sua Wii com firmware 4.3 - Pplware
How to Easily Jailbreak Your Old Nintendo Wii
MODIFICA WII - TUTTE LE VERSIONI
Modifica Wii 4.3E avvia qualsiasi gioco [TUTORIAL] - YouTube