I think you are approaching this all wrong, if it were me I would mount the center channel under the tv at the level you want... You can get a small cantilever mount for a tv and install it on the wall uncer the tv with your center channel and then move it where ever you want it... I wouldn't lift the towers, I like the center channel about listening height...
as for the sound panels, there are some companies that make them really affordable, I have never made them myself, others here have and should chime in...