is it as easy as tapping into the blinker rigth next to the grille and calling it a day?
But it's just about as easy!
Your cornering light wires are fed to the headlight harness plug next to the PCM. On 9C1's and other cars without them, the wires END AT THE PLUG! They are fully functional, all you have to do is connect up your cornering lights up to the orange and black wires at that plug. After that, ground the light wires by either soldering them into the harness ground (for a factory configuration) or ground them to the body of the car.
If you pop the headlight harness end of the plug apart, you can simply slide the pins from the cornering light wires you have in there, and pop it all back together.