I want to wall mount our 55" TV. I see mounts from $12 to $60. I don't
want or need articulating, just flat and maybe the ability to tilt.

I see you mount on the wall and a part on the TV. How do you put them
together? I will have help lifting it in place.

I also know exactly where the studs are. I have a photo of the framed
wall when it was being built and a stud is to the right of a box on the
wall. No guessing there.