I've been after this for a long time, so was pleased to find it amongst Dot Jarlett's clippings; from the Evening News, March 1969, a guided tour of Kenwood, then being used as little more than storage by John and Yoko:
Note the last Kenwood sighting of the Fool piano, which has for some reason migrated to the "library":
These have all been scanned hi-res, so download and zoom in to read.