[StreetEdition]

i recently did this with an XM Onyx radio

I pulled apart the cigaretter lighter plug and pulled out the IC board (this thing was a transformer, 12V in, 5V out) and disconnected the metal clips/spring

I then soldered some wire to the negative and postive terminals and then spliced/soldered these wires to the back of the cigarette lighter. i then put the ic board back into the casing and taped it up with electrical tape

I ran the wires up through the dash and out via the vent. used the vent mounts to mount the radio. So, all wires are now hidden and behind the dash.

I was concerned about draining the battery, but this XM radio has an on/off switch