I always thought the SR-71 was an amazing aircraft. The more I've read about it, the more I appreciate the engineering that went into it. Thought it would be a good metaphor for my '72 Mustang. My uncle worked for Kaiser Electronics in San Jose back in the '80's, and would get me t-shirts with aircraft like the F-15 Eagle, or the F-16 Falcon on it; I've always had some fascination with military aircraft.