
What’s the best way to mount on this rock wall?
I prefer not to drill in Mount directly into the rock. I’m hoping I can use the grout area, but I’m not sure that’s gonna be strong enough. What do you think?

I prefer not to drill in Mount directly into the rock. I’m hoping I can use the grout area, but I’m not sure that’s gonna be strong enough. What do you think?
I purchased a full-motion mount for my 75" TV, and it has worked great. I could slide the TV an inch or two as needed to center it on the wall. My contractor made sure the wall plate was mounted into the wood studs, but it is slightly off center. I guess he was worried about the lugs being too far to one side or the other.
I recently upgraded my TV to an 85". The TV weighs a pound less, and I am using the same mount, but the mounting rails that support it barely accept the 600 x 400 VESA format. The new TV is off-center by about two inches because of the wall plate placement.
I don't want to move the wall plate or disturb the installation. The original mount was made by Mounting Dream and said to accommodate up to a 90" TV. I don't need a new mount, just longer rails. I was thinking of purchasing their 94" mount, which supports 800 x 400 VESA, and swapping the rails from one mount to another. Has anyone else ever run into this? The mount is in the photo.
Any help or guidance would be appreciated. I would hate to disturb the current mount and have to drill more holes in the tile. The height is perfect; it is just off by about two inches.
I know the wall plate is not level. I gave him hell for that at the time.