How do you downgrade a 3.90 m33-3 psp to 1.50 custom firmware?

Question

I just ordered a Pandora Battery and a Magic Memory Stick and used it to put custom firmware on my psp. My psp used to be at 3.90. Now after I used the Pandora Battery, now it is 3.90 M33-3. And now I can play emulators and stuff on it. But, I want to downgrade it even more if its possible. How do I downgrade from a 3.90 M33-3 to a even lower custom firmware like 1.50? If I cant do that then can you anyone tell me whats the lowest custom firmware I can downgrade to and show me how to do it? Thanx

Answer 1

I tried downgrading from 3.5 to 1.5 but not sure if the procedures of downgrading it will be the same thing to your firmware. You can check the link though.

Answer 2

Go to this link and download the firmware you want.

http://www.psphero.com/download_custom.h...

You will need WinRAR to open the folder and take out the firmware..

http://www.rarlab.com/