for instance I've done a lot of usb rewiring. I'm betting your motherboard has 4 pins(used) 2 usbs have 10 pins but key takes one then there were 9 and one is not used) per usb connection the red goes to the +5 pin, the shield and black goes to the ground pin. (Off the top of my head) Green goes to +data white goes to -data. FireWire shouldn't be much harder to figgure out. switch.. 2 connections polarity will not matter, leds 2 connections polarity will matter but if you get it wrong, the led won't light and all you have to do is reverse them, no harm done. Anyone who has a suggestion on the audio chime in here I could stumble through but I'd rather hear from someone who has done this before.