James "Cubby" Culbertson wrote:

I know. Unfortunately, I have a tile floor and tile baseboards (saltillo).
A plastic moulding won't work for this especially
as there are 8' openings as well to somehow traverse. Unless I dig into
the walls or tile, I'm pretty well stuck with wireless options for
rear speakers.

Sorry. I meant tile and wood moldings exactly like the ones
you have, or you can alter some yourself if the tile is thick
enough. They also make flat cable.