Like I said, if you REALLY want to do it, you can (provided you have a PS2 to get the bios from) run it in PCSX2 through the TexMod program. TexMod will allow you to replace textures while the game is running, BUT, PCSX2 is mildly difficult to setup for the first time, and will have a very low framerate/ or run very slowly.
If you just want to take a few screenshots with your new texture, that is the way to do it.