If you find a way then please let me know!
Here is what I'm testing and may use...
in the CUSTOM SETTING MENU> f Controls> f2 Custom controls (shooting)> (Fn2)> Live view info off>
I hope that makes sense. (Fn2) is the button i chose.
Here is what happens...
Pressing (Fn2) toggles "Live view info" off then on. All of the info on the monitor and in the viewfinder disappears except the focus area marker(s) giving a very clean monitor or viewfinder for composing the shot.
Dave