I'm assuming you're bumping because the original question was not answered to your satisfaction. Why don't you just pull the wires from both the original plug and the new loose wires (NOTE: Please wrap each wire with a piece of masking tape first and write on the tape what the wire is. It should say on the plug you are removing) by using a pencil tip or something and then swap plug ends making sure the new case wires follow the pinouts all ready pointed out to you in the above posts.
Now your new case has a solid plug and the old case is still usable by some one else, if needed, since everything is labled.
This option does not involve $.