Cantilevered pillar TV mount extension
I would use two or three &quot;max brackets&quot; with a simple wooden structure attached. Select the largest size that fits the depth you need (factor in the wood face plate thickness). I like black as they aren't so conspicuous.

Mount these with three 5/16&quot; x 2-1/2&quot; lag screws each, into framing. Then screw 2x4 rails to each, on edge, and a 2x8 rail across the front, using the same screws. Pilot with a 3/16&quot; bit. Like so (side view):
                               __
                              |  |
 ____________________________ |  |
|        2x4 top rail        ||  | &lt;-- 2x8 (or 3/4&quot; plywood) face plate
|__________________________  ||  |
|                    *        |  |
|                *            |__|
|            *
|        *
|    *
|*
|

Use lag screws into the horizontal rails and to attach the front plate also. Those in the front plate should be countersunk just below flush so they don't interfere with the TV mount.
If your TV mount point is low on the unit (like with my LG glass model), Use 3/4&quot; plywood instead of the 2x8 and extend it downward 12-16&quot;. This will allow you to move the brackets up and out of sight. You might also upgrade the top rails to 2x6 to reduce the torque of the front plate on their ends. If you see too much flex, run diagonal braces up to the sides of the top rails:
 ____________________________  _
|                  \    \    || |
|____________________\    \__|| |
|                    * \    \ | |
|                *       \    | |
|            *             \  | |
|        *                   \| |
|    *                        | |
|*                            |_|
|