I have to run pvc across the ceiling of a front porch because there is no way to snake it without tearing out. The question is what kind of a box can be used to hang the ceiling light on that will work with pvc. I think the base of the light will be about 6". I'm not sure a metal wm box would work...they aren't really made for exterior use. Possibly a pvc wm box, but I can't remember seeing any wm boxes that would accept a pvc adapter.