I went to a pawn shop and (finally) they had some DCs in so I bought one ($15 not bad)! Before even testing it too see if it works I opened it up and to my surprize (not!) the case had plenty of room inside for fitting the controlls.
So heresisat I have planned for it: Original DC case for a case( shocking!!

), flip up, removable, 5 inch PS one LCD, 8 AA's for power, unofficial controller with a modded PS one anaolog stick replacing the crappy one (a lot like Dave's DCp), probably rewire the the VMU to the top of the cd lid, and thats about all I got plans for right now.
Power is where I am stuck, I was thinking I could buy some voltage regulators (12v,5v, 3.3v) and that would work, but do I need capacitors in front of the regulator?
Or maybe I could use a GC power board like Gamelver thought of?
Anybody know what dave used? I'll try emailing him when I get my PC back from the shop