 The 20th Anniversary Edition GT350's were produced during 35 days of production.The entire production is believed to have been done in 35 batches starting March 5, 1984 and ending in April 1984, there was one final Anniversary Mustang Convertible (TBI/CFI Automatic) Produced on June 12, 1984.There was no official 25th Anniversary model from Ford in 1989, even though this was looked into with several designs on body and performance modifications.