Check out the empty slots first. Use a voltmeter to see if they turn on with the ignition. Running the wire down the a-pillar is not difficult. In fact it's easier to pull off the a-pillar panel than trying to run the wire down some little rubber weatherstrip. There's 1 bolt holding it on behind the airbag tag, and that's it. There's tons of wires behind that panel... where do you think the wires for the lights etc. come from?
Heck, if it's too much of a paint then just pay a good stereo shop to do it, it's a cakewalk for them to do detectors.