h/d power - modification question

i'm thinking about adding a toggle switch for my 2nd h/d so i can turn the power off (when the computer is off). has anybody here done such a thing? does anybody know what the voltages are, and the colors (red, black, black, yellow)? i'm sure i can figure that part of it out, just being lazy. basically i've had to reinstall my os a couple of times here recently, and it would save me alot of time, of moving my comp desk, unplugging everything, and opening it up, to disconnect the 2nd h/d. any ideas or suggestions? - sos

 

why not use these...
http://www.geeks.com/details.asp?invtid=GN210&cat=CAS

You can pull drives out & turning the key turns power off & on also.