I have a 2009 Mac Mini with the new style power switch cable, but the MacPac cable I have is for the pre-2009 models.
I can't order a 2009 cable from the MP3Car store as it is $50 shipping for a $10 cable

I think I'm going to need to cut the old style connector off the Y cable and solder it to the back of the power button in parallel.
On the Mini PCB, one wire is marked as V and the other as J4801.
The P2140 wiring diagram for the outputs on the old style MacPac cable show the switch is connected to Grn (ACPI) and WHT (iSNS).

Does anyone know which way around the wires are supposed to go?