Hacking together a power button assembly?

I have a powermac G5 with a busted I/O (power button) assembly. I don't really need the front FW/USB ports or even the light- I just want to be able to turn it on without opening up the case!

Is there any way to permanently connect the button to the corresponding pins on the motherboard? Even used boards are fairly expensive and most don't even include the cable, which I would also need.

Any advice is appreciated!