I'm in the process of doing it and will post my progress once I get a breather (work!) and can focus on it.
I intend to manually swap between my IPAC and the hacked DC controllers (my CP is swappable so it can easily be disconnected from the IPAC anyway).
Video will be a manual switch until I can get some assurance that a KVM will not be a problem with a DC video source (and no K or M) and that video quality can be maintained.
I'm hacking my own controllers. You can either use standard controllers and follow the tutorials referecned in this forum, or you can do what SNAAAKE suggests and hack PS contollers and then use a PS/DC converter. I probably should have done / should do that.
That's about it. Read down a few threads. This is all discussed already.