Judd Nelson was a pretty big deal back in the 80's having been part of the 'brat pack' group of actors who starred in a lot of the teen orientated movies back then. His casting as Hot Rod would have been to lend some of his 'star power' to the 1986 film. Unfortunately like most of the brat pack his popularity peaked in the 80's and he is not that well known today.
However none of this is important as this story is probably not based on fact. Can't wait till MSN catch onto the "Judd Nelson has died" hoax of late 2014 :rolleyes: