Addendum from Matt 4/22/10: "There is some kind of discrepancy: According to the FAA registry, your Dad's N1154H was/is serial number 15AC-167, while the "City of Yuma", registered as N1156H, is serial number 15AC-166."
So, it would appear that our Sedan and Yuma were twin sisters.
"A Sedan was chosen by pilots Bill Barris and Dick Riedel for their attempt to set a time aloft record in 1949. Their flight was sponsored by the local chamber of commerce and the Sunkist growers association, the second sponsor accounting for the naming of the aircraft as the Sunkist Lady. (The accompanying support aircraft, also a Sedan, was called the Lady’s Maid.) Departing from the Fullerton, California, Municipal Airport on March 15, the flight crossed the United States to Miami, Florida, where bad weather forced the pilots to circle for 14 days before making the return trip to Fullerton. Along the way, fuel and food were passed from vehicles on the ground to the pilots during low passes over airport runways. Having reached Fullerton on April 11, the pilots kept flying around the local area until April 26, finally landing at Fullerton Municipal Airport and setting a record of over 1,008 hours, or 42 days, in the air.
The Fullerton record was short lived. Inspired by the flight at Fullerton, later in 1949, Yuma, Arizona, decided to sponsor its own time aloft record attempt. The city needed publicity as it was experiencing economic hard times due to the 1946 closure of Yuma Army Air Field. Pilots Woody Jongeward and Bob Woodhouse piloted the City of Yuma, a Sedan borrowed from local owners, modified for the flight and painted with the slogan, “The City with a Future.” The flight began on August 24, with the aircraft remaining in the Yuma area throughout, and ended after more than 1,124 hours, or nearly 47 days in the air, on October 10. In 1997, the record-setting airplane was located and returned to Yuma; made airworthy again, it flew on October 10, 1999, to commemorate the 50th anniversary of the end of the record flight. The "City of Yuma" airplane is now on display at a museum in Yuma."