Step 1- Downgrade your ps3 to 3.55
Step 2- Install Custom Firmware to 3.55
Step 3- Install Any dex or rebug Firmware
Step 4- spoof to any dex firmware you would like
Step 5- You are done now that you are on dex you dont ever have to update again
If needed for more explained version comment down below and i would be happy to help
Hope this helped Enjoy!!!!!!
Step 2- Install Custom Firmware to 3.55
Step 3- Install Any dex or rebug Firmware
Step 4- spoof to any dex firmware you would like
Step 5- You are done now that you are on dex you dont ever have to update again
If needed for more explained version comment down below and i would be happy to help
Hope this helped Enjoy!!!!!!