I am creating a custom fileserver from an old case and parts. The mod involves cutting an old case down to about half-height, adding a white plexiglass shell to the chassis, and making it all really quiet. I am modding an 8-port network switch into the case and I will have room for eight hard drives. So basically I am looking at having at least 20 indicator LEDs on the front of the case, 8 of which are dual color from the network switch. I have a handfull of BC337 NPN transistors and I would like to implement them in an LED indicator blackout feature. How do I do this? Do I need to put a resistor on the emitter of each transistor? Any repercussions in the emitter being hooked back into the network switch's board? Do any of these questions make me sound like I know what I am talking about? Please advise!