Here's my $0.02 worth. I have a 1966 Mustang that had a factory 289 (later pulled for a 302 which will be replaced by a 351) which was painted black. It confused me because up to that point, I thought all Ford engines were blue, and every Mustang engine or Hi-Po Ford engine I had seen was painted blue. According to my various Mustang and Ford books, Ford engines were all painted black from 1958 to early 1966. Sometime during the 1966 model year, it was switched to blue. Heck up to 1958, Y-blocks were painted red (try explaining that one to your Chevy friends).
Just my attempt to add to the confusion. /ubbthreads/images/graemlins/wink.gif