The pemnuts are on the front tub where the stock bumper brackets mount. I fabricated a tow hook mounting bracket from angle iron and a nut welded to the angle iron. Bolt the fabbed mounting bracket to the pemnuts in the tub and hole saw your spoiler in the just the right spot.
My threaded tow hook was 15$ and the hole saw was $10. Now the question is are you going to mount it on the right or left side of the car, let your politics guide your choice