The connector is a 20 pin IDE style (i think thats right), and diagrams exist as to which each one does. So I think i'm going to give it a try this weekend to atleast use it as an external monitor, then the next step would be to be able to switch back and forth. A note to anyone else who wants to try this, the computer will not start up unless the cable is connected to the logic board, you can pull it out once it is started up, just not plug it back in.
As for with a G4 iMac, i know it can be done becuase a prof of mine at school had his old winblows computer running using his imac screen as the monitor, don't know how he did it, i'll try to find out.