One for sale in 2004:
http://www.sspmustang.org/forums/showthread.php?t=142 Could possible be the same one.
chism and friend found one here:
http://www.specialservicemustang.net...ead.php?t=4961
Only group of 28 is MF170431-MF170458. .ORG claims there were 69 used that year. Perhaps the group of 40 immediately preceding the 28 are also Nebraska?