emusonacid! legacy

Ok, so I have set myself a project of building a cf card reader for my sampler which is an esi4000. I am totally clueless so any help would be appreciated.
I already have the card reader and I am deciding which scsi to ide bridge to buy. I also have a full card reader unit from scsi4samplers so I am trying to reverse engineer from that.
My first question is about the power for the card reader and the scsi bridge. On my scsi4samplers internal unit, the power is supplied from the floppy(5v) on the motherboard, this cable seems to devide after it goes into the bridge leaving another cable to power the cf card reader. So in summary the motherboard appears to power the bridge and the card reader.
so is this possible, one 5v cable from the motherboard powering two seperate devices which both need 5v to run?
" http://i744.photobucket.com/albums/xx83 ... off/cf.jpg "