Yes, I'd suggest you use my "How to soft-mod a pandora battery" guide located here: http://www.codinghs.com/forums/showthread.php?t=1651
It explains how to make a pandora battery with a CFW enabled psp, which can be turned back to normal with the same program I provided in the guide.

EDIT: and yeah, I believe the GoW slim can be hacked the same, Who