If it was "complete" it woud have given us more information than"sold in Nebraska".
Could the name have some relation to the University of Nebraska nickname BIG RED.I don't know but it is in interesting idea.

4-2-2005 - We have rec'ved some information on the Big Red Special from David an owner of a 1970 sidewinder mustang owner." While studying on the 70 sidewinder mustangs I met a guy named (name removed) from Lincoln,Nebraska.The big red special that he had was a 1970 sportsroof red in color , 302 2v,auto transmission, sport mirrors and the ford corporate caps with trim rings. Here is a picture of the car in the mid 90's.