A very sad day for both MG and Triumph. In July 1979 the British Leyland boss Michael Edwardes and his senior management met at Ye Olde Bull, Hurley, Berkshire to discuss BL's worsening financial situation. At that meeting it was decided to cut the BL workforce by a further 25000 workers. It was decided to close the Triumph Factory at Canley and to cease MG production at Abingdon and with it the end of the MGB.
Further information can be found here http://books.google.co.uk/books?id=csZRy1YY0_EC&pg=PA71&lpg=PA71&dq=ye+olde+bell+hurley+mg&source=bl&ots=mr5Bil4orn&sig=aFeyg2PlBHjNF4nrZB8jrVZNocg&hl=en&sa=X&ei=fabVUNm8IKSR0QW-noGgAw&sqi=2&ved=0CGkQ6AEwBA#v=onepage&q=ye%20olde%20bell%20hurley%20mg&f=false
Correct. They actually became the first non Italian team to win the team prize. Although Birkin retired no other team finished without a retirement. Source MG by F Wilson McComb