Yet another continuity tester

PC's even dead ones are a wealth of parts. I was out at a site and they asked me to do some troubleshooting, but would you not know it, I did not have my tools with me. They did have a dead pc about to be trashed. so I borrowed a part or two to make the tester.
Note: This setup may not work well with very long wires.

Step 1 Gather the parts.

You need:
    Bios battery holder removed from a dead motherboard.
    Led from front panel of computer
    Two wires from led to motherboard separated.
     Bios battery (working).

Battery holder can be easily desoldered by melting just two points. (battery must not be installed)
The led and wires should be easy to dismantle.
Battery should be good, if not they are cheap.