It was an attempt to reverse the trend toward ever-increasing weight of the Liberator as more and more armament, equipment, and armor had been added, with no corresponding increase in engine power. With the weight reduction and more powerful engines, it also had a much longer range than earlier models. 1250 B-24L aircraft were built at Willow Run. The B-24M was the last large-scale production variant of the Liberator. Apart from a new tail turret, the B-24M differed little from the B-24L. The first B-24Ms were delivered in October 1944, and by the end of its production in 1945, Willow Run had built 1677; 124 Ford-built B-24Ms were cancelled before delivery. Ford had switched over to the single-tailed B-24N in May 1945, but the end of the war in Europe in the same month brought a rapid end to Liberator production; the contract with Ford was officially terminated on 31 May 1945 and orders for 5168 unbuilt B-24N-FO bombers were cancelled as well. The delivery of seven YB-24Ns by Ford in June 1945 marked the end of Liberator production at Willow Run. Post-war conversion Although Ford had an option to purchase the plant once it was no longer needed for war production, the company declined to exercise it, and ended its association with Willow Run. Kaiser takes control After Ford declined to purchase the plant, it was sold to the Kaiser-Frazer Corporation, a partnership of construction and shipbuilding magnate Henry J. Kaiser and Graham-Paige executive Joseph W. Frazer. The plant produced both Kaiser and Frazer models, including the compact Henry J, which with minor differences was also sold through Sears-Roebuck as the Allstate. Willow Run produced 739,000 cars as part of Kaiser-Frazer and Kaiser Motors, from 1947 through 1953, when after years of losses, the company (now called Kaiser Motors after Frazer's exit from the partnership) purchased Willys-Overland and began moving its production at Willow Run to the Willys plant in Toledo, Ohio. Although Willow Run is synonymous with the Liberator bomber, B-24s were not the only planes manufactured at Willow Run. As the US Air Force struggled to expand its airlift capacity during the Korean War, Kaiser-Frazer built C-119 Flying Boxcar cargo planes at Willow Run under license from Fairchild Aircraft, producing an estimated 88 C-119s between 1951 and 1953. Kaiser also built two C-123 Provider airframes at Willow Run, which were scrapped before delivery, as a procurement scandal