After some research, I decided that my FlyLEDs landing/taxi lights don't need the angle-adjustment capability of the W-00016B bracket since my plane will be tricycle gear and not tailwheel. Therefore, I just needed to mount the FlyLED circuit boards directly to existing W-00017 mount bracket by adding two nutplates on each side of the hole.
So I started by de-riveting the existing W-00017 mount bracket to make access a little easier. This would also allow me to remove the now unnecessary nutplates on the sides that would have attached the W-00016B bracket. Then I drilled the centers for the screwholes and added the new nutplates on the bracket face, and then re-riveted the brackets into the outboard leading edge wing sections. I'll leave the circuit boards unconnected for now, just to prevent accidental physical damage.