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?