I'm sorry for reviving such an old post (is that something ok to do?) But I'd like to ask OP if they were successful in editing the save file, I'm trying to do the same.
I went to a garage sell last saturday, and the lady had a PS2 for sale, but she had a sign on it that said "Nintendo -$50", had to laugh, almost bought but she didn't know if worked, and she didn't have controller or cables, so I passed.