If my dremil skills were better then I would have a stab at butchering a cheap pc case lol. I am in two minds if I want to go down the mediator route with this system. Dunno if I would get the use out of it though. The case mod was part of the decision process.
Question! Since the cost is going to reach you the same level as owning an Amiga 4000D or Amiga 4000T. Why not leave your A1200D the way it is and simply buy an Amiga 4000D or Amiga 4000T?