Interesting, particularly from the whif point of view, unbuilt Crusader variants from the new Specialty Press book:
VFA Crusader with more attack capability and a second hard point under each wing
All-weather F8U-2 with slightly larger radome, no guns, and carrying Sparrow III's
All-weather two-seat in tandem version of the F8U-3 proposed to Canada
Has a good bit on the evolution from F-8 to A-7, too.