Power from cig lighter

[p3eps]

I was trying to hard wire my Micro Roadpilot today...

My aim is to have it in the ashtray (non smoker pack) cubby and hard wire it to the underside of the cig lighter. 
I ran the GPS antena up under the light sensor / vent like advised in other threads... but am stuck with which wire goes where for the power!!  Unfortunately I dont have or have access to a Multimeter at the moment - so can anyone advise which wires on the underside of the lighter socket are which?

Cheers...

[p3eps]

I've just been reading the Roadpilot manual...
I have 2 wires - a red (12V+) and a black (negative).

I've been scouring around various forums trying to find an answer as I'd quite like to get it done this morning!
I've found that the middle cig lighter wire (brown / black) is the switched ignition.  Will it be my 12V+ - as I want the unit to go off when I turn the car off?

This post here: http://uk-mkivs.net/forums/thread/498738.aspx has people doing the same sort of thing - but they're using both switched and permanent live... why?  They have no mention of negative.

I'd rather take the wires from the lighter - as thats where my power cable currently is... although I'll go for the fuse box if its easier and wont void my warranty!