a lot is mentioned here about the companies:
http://www.library.unlv.edu/hughes/pages/aircraft.html
http://en.wikipedia.org/wiki/Hughes_Aircraft
not a word about LED modules but why should they?
many key producers of electronics tried their chance in new developing market segments (National Semi., Fairchild, etc.) just for the money, not because of personal interest in watches. such companies also bought out other entities already in that particular segment to save on R&D.
Howard died in 1976 and at that time dozens of his companies and individual company departments were run autonomously so it's very likely that he only heard about Hughes LED modules from an annual report on revenues