Wow that's a big screen to put that high. Make sure you angle it for best viewing. LED's really should be viewed straight on or you'll lose the blackness and colors will fade with off viewing angles.
I'm assuming that's the only place you can put it, for the best viewing is eye level when sitting down.
You may find your neck starts to let you know how long you've been viewing.
Depending on the weight, four men should do it. I'd suggest having something like a really sturdy table with support under the table for additional support may work. Something the men can get out of each others way on.
Anyway, best of luck with the install and viewing down the road.
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