I just bought a PSP slim and want to emulate it because my PSP Phat broke. I know how to emulate perfectly fine with a normal PSP but when it comes to a PSP Slim Im confused on all the guides. What exactly do I have to do to my battery? And do i have to downgrade first? Or can I upgrade from 3.73 to Dark Alex's 4.01 M33 Firmware without doing anything to the battery?