Shelby GT - 500 with 427

In 1986 I went to a car show in Lafayette, La and saw a 1967 Shelby 
GT-500 with a 427 engine, Blue with white stripes and black 
interior.   The 427 was optional engine, but most sites list it as 
undocumented change.  Anyone else ever see one themselves, not just 
hear about it?

Trying to track this one down since I did not buy it when I had the