According to Alexander Gough's Will, he was entitled to benefits under the will of Richard Dick, who was presumably either his father-in-law or his brother-in-law. His wife appears to have been Ann Dick and he named one of his sons Alexander Dick Gough.
Alexander married Mary (Ann) Booty on 21 November 1786 at St. Giles in the Fields. The original record is not visible on www.ancestry.com so it cannot be said whether he was a widower, nor whether he was first married in 1783 to Mary Johnson - important as this would assist in locating his place of birth. Are there any source documents for this location being Bicester?