The Rivet Top prototype moved to Korat RTAFB along with the College Eye Task Force in October 1967. Originally scheduled to return to the USA in February 1968, because of its value it remained at Korat until 1969. Flying daily missions through its testing period, it began flying every-other-day missions over the Gulf of Tonkin after 31 March 1968, when Rolling Thunder ops were sharply scaled back. Rivet Gym installations were back-fitted to all College Eye EC-121s by the end of May 1968.