be retired. The Army decided on the M60A1 as the service's interim successor until the M3 Bradley was ready. At the time, 567 Sheridans existed in USAREUR, 535 in the continental U.S., and 41 in the Pacific. The Army began converting units in Europe in 1978, and in the rest of the service by 1980. The Army sustained 140 Sheridans in the 82nd Airborne Division and the National Guard. Some Sheridans were kept in pre-positioned reserve. Several attempts to improve or replace the Sheridan have been made over the years since it was introduced. In 1976, DARPA (followed by TACOM) initiated the High Mobility/Agility (HIMAG) program. Several concepts were pursued, including the High Survivability Test Vehicle – Light and the Elevated Kinetic Energy gun system. The latter was trialled on a Sheridan hull in 1982. Following the Iran hostage crisis, the Rapid Deployment Force concept was pursued by both the Army and the Marine Corps. The Marine Corps initiated the Mobile Protected Weapon System (MPWS) program. In 1983, the Naval Surface Weapons Research Center Laboratory mounted a 105 mm caliber gun onto a Sheridan chassis. The Army initiated the Mobile Protected Gun program, and announced plans to modify Sheridans with 105 mm or 120 mm caliber guns. Neither program was pursued further; The Army project was canceled in 1985. From 1978 to 1980, under the joint Army–Marine Corps Advanced Antiarmor Vehicle Evaluation (ARMVAL), TACOM rebuilt 10 Sheridans with the General Motors 8V53T diesel engine and improved suspension. The vehicle's armament and some armor was removed. The uprated engine and improved suspension improved the power-to-weight ratio and cross-country mobility. The Army also evaluated a fully stabilized Staget sighting system. In 1987, the Army tested a version of the LAV-25, classified as the M1047. The Army determined that these were unsuitable for LAPES, and could not match the firepower of the Sheridan. Congress did not favor the M1047, though a few were deployed with the 3/73rd Armor in the Gulf War. The Marine Corps also developed the LAV-105 to meet its requirements, but later canceled that project as well. In 1992, the Army selected FMC Corporation to produce the Armored Gun System (AGS), later type classified as the M8 Armored Gun System. The AGS was canceled in 1996 by the Pentagon before it could enter production. United Defense proposed the AGS as its mobile gun system variant in the Interim Armored Vehicle