i have a flat desktop tower instead of a tall one so looks like a vcr ok... I am trying to figure out where the hdd led plug and the sw power and theres two for each pair plus a green wire and white wire >>>>
Unfortunately, there is no standard for identifying the polarity of front panel wires. As a rule, the common color, usually is ground.
For power and reset switches, polarity does not matter.
For led's polarity does matter, but ho harm is done if you connect them wrong, the led just does not work. Reverse the connection to make it work.
One is a hard drive light
One is a power light
One is a power switch
One is a reset switch
As geo said, the common colour tends to be ground so if most of the pairs have a black wire, it will most likely be the black, although I helped someone on here recently whose fourth pair were both odd colours, luckily it was an led wire and as such subject to the trial and error method.