Chapter II - Hardware Needed for PS3 Downgrade | PSX-Place
Compatibilita' - JUCETIZE
Jailbreak Ps3, This is not needed but it is highly recommended to have the latest firmware installed on your PS3 to make sure everything will work properly.
Evilnat 4.89.3 PS3 CFW Released! - Hackinformer
Katalog Game PS3 Rev 2-Excel | PDF | Leisure | Sports
Downgradable PS3 Models & Base Firmware with MinVerChk | PSXHAX - PSXHACKS