I am no stranger to downgrading a PSP, I've done a few with my own such as from 2.0 to 1.5 then up to various versions of DA's custom firmwares with 3.10 OE A being what I have now. Now I have a friend who is really not capable of doing such things to his PSP. Usually I wouldn't need any advice but since he has a TA-082 PSP with 2.8 Firmware I am not sure how to go about this. Having never had the curse of the TA-082 PSP and always being on firmwares that can be easily downgraded again leaves me in the lurch somewhat.
I understand that now TA-082 PSP's aren't the curse that they once were and can be downgraded easily nowadays. My limited knowledge also has it that a copy of the unpatched GTA LCS UMD is needed and I have that so no problems there. What I am asking for here is to be pointed in the direction of a good downgrader, one that has the least amount of chances of failure as well as a good guide for it. Since this is my friend's PSP I wouldn't want to leave him with a brick. I presume it would be a downgrade to 1.5?
Obviously I will be wanting to install a custom firmware after the downgrade, I've only gone as far as 3.10 OE A on my own PSP so are there any newer versions that still allow for the same functions as 3.10 OE A? I am merely asking for suggestions and a general direction to go in, I don't expect you guys to do all the work in regards to my requests like handing me links to every little detail.