You could pull the turn signal bulbs (front left and right) and tap the wires that feed the +12 volts to them, not sure which one of the two wires feeding each bulb is the hot side and which is ground, bit that would be easy to figure out with a voltmeter with the turn signal turned on.
My main question is why do you need to add side repeater turn signals? Funny you mention them, on the same day you made your post, I saw a late model car that someone had added them to and wondered what the heck was up with that?
