Take a 3v lithium battery (like the one on your motherboard) and you can make a tester out of it. Take some phone wire or something similar (cat3, cat5), strip about a half inch off each end, and tape one wire to each side of the battery. ...a foot of cat5 Ethernet cable would work good since it's usually a solid wire. You can pull out one twisted pair and your homemade tester will be color-coded. Use the other ends of the wires as a probe to check the front panel of your case.

Using the pinout on Rob's site, find the proper slots in the connector to your front panel and check to see if the LED's are the same. Stick the + wire in the + port of the connector and the - wire in the - hole and see if the appropriate LED comes on. This is the method I used to find the right wires. I used an ohmmeter to find the proper wires for the switches. ...just connect an ohmmeter lead to each lead of the switch and you should have an open circuit. Press the switch and you should get near 0 resistance.

As for the headers, I think you need the 2.54mm double headers (910-1530). You'll need to break off a double row of 4 headers. The header pins should fit into the little connector attached to the ribbon cable, and you will probably have to solder the new wires on the other side. I'm not sure what kind of connection the headers have, but I imagine it's a solder variety. I had the motherboard connectors lying around, but I don't know where you'd get them otherwise. I didn't see them in Radio Shack's catalog. Maybe www.digikey.com will have something. You don't necessarily have to use the Radio Shack headers either; it was just something I looked at.

I wish I hadn't thrown away the ribbon cable so I could take a picture of it. The wife frowns on me leaving that stuff lying around in the living room. The ribbon cable comes from the front panel of the case. The other end plugs onto the connector on the motherboard. The fitting looks a lot like a standard IDE or floppy connector. The Radio Shack headers should just plug into that connector and you wire from there.

I really think Dell probably has the same connector throughout its line. ...but I haven't looked.