how do i make my slim 3.60 official to 3.90m33-2 (pandora?)

hey guys, i have an original slim 3.60 official sony frmware. i wanted to get it to 3.90 m33-2. do i need to get it to 3.60m33 first and then to 3.90m33? if so do i need a pandora battery for this. I was able to update my fat psp to 3.90m33-2 without a problem(and without a pandora battery). i wanted to do the same with my slim. Any help would be greatly appreciated. Thanks fellas.

ok you do need a pandora battery or a datel tool battery to put cfw on your slim psp there is no other way to do it and you dont need to go to 3.60m33 first...i went stragiht from 3.60 ofw to 3.71m33 the to 3.8m33-5...you can then just upgrade to 3.90m33 from there

Thanks man. Now I gotta find someone with a p. battery.

where abouts do you live