I want to as well...but I'm going to wait until someone else does the hard part and makes an install diagram! xD Is there even room to cram the PSIO board into a PSOne slim? I've never opened one...
so until rave does it, jk XD theres room, but just barely, also to me it wont matter cause i'll be making a handheld.
I think they are still planning on internal-only mod for 9000 series and PSOne series . I haven't been watching PSIO scene since I sold my stuff a couple months ago.