I have my PS just laying loose in the bottom of the box. I used two pieces of leftover pvc cut to fit length wise in the box. They next in two grooves that hold them in place. I screwed on side of my hub to one piece of pvc and let the other just rest on top of the second piece. I caulked the vent holes just on the outside and used a little black spray paint on the caulk when it dried. Never got any water in the box even in pouring rain. Most of the time I forget to latch the top down and it has never come off by itself or from wind.
