The guide talks about appropriate downgraders depending on what version firmware you have. Problem is, I don't know what version I currently have, nor do I have the PSP box it came in to check. My question is: I have the 1.50 firmware downloaded, can I just copy it to my psp and overwrite? Or do I need to find out what version I have and get the appropriate downgrader? If so, what is another way to find out what current version firmware your psp is using?