Looks good. I would have recomended against painting the tubes before you cement them. If you use a pvc primer before the cement it will likely strip the paint, and if not it may not bond properly. I would also recomend a good plastic paint. It has a special formula to make it bond to plastic so it wont flake off under stress.
I did a very similar project last summer by the way.
I never did figure out a way to rig up a bracket but it hasent hurt anything yet.
By the way, although this may be ignorant, of what power wire do you speak?
Mods: Thule Xsporter 422XT bed rack, Underrail Rhinolining, MOPAR class IV Hitch, DIY CAI, Aero Turbine 3030.
Future Mods/Wishlist: Tuner, Daystar Comfort Ride 1.5" Leveling kit, Nerf Bars, Police style push bumper with light guards, KC or Thule trail lights, HID projector lights.