Page 1 of Speaker Brackets???

I have a pair of bookshelf speakers (weighing about 8kg) which I am looking to stick up on the wall of my kitchen/dining room, and angle them down slightly. I don`t want the type with a base on them, or clamps, as I want the bracket to be hidden.

I thought I had found a pair (Atacama Matrix) which would be ideal, however, the speaker has a port on it above the connections so the bracket would have to sit slightly off-centre, and i`m worried the weight would twist the bracket if not totally centred.

Has anyone else had this problem and overcome it? Anyone know of a bracket that would suit, as I have trawled the net in search of something suitable but with no joy, yet?