'Sony Wirefree' aside, [ which looks really good at that price, they're $800 here! ], where are the windows, Ian? Always a problem with a tv on an inner wall is reflection on the screen and sun glare.
Suggest a few test-runs [with Mom involved, please, it's her home!] at chosen locations in daylight before you start eagerly tunnelling into the plasterwork! And don't forget you also need some electrickery for the doohickies!
Practice your 'totally horrified look' in the mirror, in case "run it under the carpet" gets mentioned! [Linked Image]

Alan

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[This message has been edited by Alan Belson (edited 12-05-2006).]

Wood work but can't!