Installing a back up light

I put one on my Baycat trailer. I drilled into the second trailer cross member from the back and bolted it on, hanging it down rather than on top of the cross member like they come from the factory. I ran a ground wire to the ground for one of the tailights. The power wire needs to be spliced into the blue wire coming out of the trailer tongue. Thats the wire for the solenoid that locks out your brakes when backing up. I ran a wire along the trailer frame up to that blue wire in the tongue. Theres probably a better way to do it, but what I did worked. Eventually…I plan to put a couple of back up lights on my new Cougar trailer.