ok so i have an extra radar detector lying around and i'm gonna put it on my bike. i took it apart, and now i figure i can take the 2 wires that run to the speaker, and run them too an l.e.d. and then mount that l.e.d. to the dash. will it work?

 

I guess the speaker signal is to weak to drive a LED so it can be seen in daylight and when your focus is on the road. It may glow some though, even if the speaker output is AC and the Light Diode works on DC. What you can do is to amplify the signal and then drive whatever you want, a relay, lamps, LED's etc. If you search for voice activated switch and similar, you'll get ideas and inputs for solutions. E.g. http://www.gatewayelex.com/kits4_F.htm

Isn't there any diode already on the unit that can be relocated?