If your PS3 ever gets stuck on the dreaded 99% update while in the loading scream here's how to fix it without losing all your files.
First get a cleared second hard drive.
Then have a USB with the Newest update.
After that just install the second HDD as if you were starting from nox.tips/ .
Once installed and on the XMB, turn off your PS3 then take out the second hard drive and insert your original hard drive.
Finally once you turn on your PS3 with your original HDD, you will see that you got it out of the 99% update loop and all your files and Games will be intact.
I hope this helps anyone if this ever happens to you.