The data for 1984 is significant because it is the last IH build Cub Cadet tractor. In this case, you can say that the last one built was "red" because that is the only color that IH painted the *82 series tractors.
The last Cub Cadets built by IH were built in 1981, not 1984.The last IH built 482 and 982 were built in Feb 1981, the last IH built 582, 582S, 682, and 782 were built in Apr 1981. CCC built the red 82 series tractors to be sold by the IH ag dealers from 1982 to 1985 (1985 model year), along with the yellow and white versions for sale by Cub Cadet Lawn Power dealers.
145782399 is a Factory Number used by CCC. It does indeed identify that tractor as a 782 built for IH in 1985. The 145 = the model year 1985, 782 = the model or "Hood Decal", and 399 = IH. If that factory number ended in 100 rather than 399, it would mean the tractor was a yellow and white version. The serial number range used for 1985 was 737,625 to 747,224, and that range included ALL
82 series built in the 85 model year, including both red and yellow and white models. There was also a "Kind Code" used for the red models that also identified the model.
The year codes used by CCC for the 82 series is as follows: 142=1982, 143=83, 144=84, 145=85. The Serial Number range was different for each year, but to my knowledge there is no way to tell what S/N was used on what tractor/what model/what color.