Jool, I've spent so many hours on this one! If only I was this dedicated at work! Thankfully I'm now retired so my time's my own. I've travelled many a road on google map, searched so many websites, I'm fresh out of ideas. I can only suggest it's been demolished, or well hidden on a country estate (?), or possibly bombed in one of the wars. Not given up though, still painfully daily searching......