On his son George's baptismal record on 1757, William is called William of Long Furlong. Long Furlong is 1.3 miles south west of Tetbury.
By Jan 1760 William is living "Dufton" [or Doughton in modern spelling] which was 1km from Long Furlong. Today, between these two places lies Highgrove House, although this royal residence wasn't built until 1796.