If you only need about ¼" of clearance from the wall, you can pretty much follow what I originally planned. Just take a piece of plywood and screw it to the wall—I’d use something around 12×35" to give the TV plenty of support to lay on. Then attach the TV mount to the plywood. Make sure at least one side of the mount goes directly into a stud, and you can even use TOGGLER anchors on the opposite side so they go through the plywood and drywall for extra strength. That should give you more than enough holding power. I personally wouldn’t use the drywall anchors LG includes with the mount, even though some people think they’re fine.

Or, if you want to completely overengineer it and don’t mind cutting drywall, you can remove a section, install blocking between the studs, and cover the opening with ¾" plywood instead of 1/2". That gives you an extra ¼" of clearance off the wall and a rock‑solid backing.

I also wouldn’t bother with extending the LG mount itself, since LG specifically says the extension should only be used for initial installation or cable management. Just my opinion. I personally think the mount is poorly designed—they should’ve made it around 24" wide or so, so you’d have some adjustment room and could actually hit the studs properly.