Back in the 1990's, I saw a guy with a Mustang...with lines I didn't recognize on any current Mustang of the time. The guy in the Mustang looked like an engineer...you know...short haircut, pencils and pens in his shirt pocket, etc.
He had Michigan MFG. plates on his car. This was in Canada. He also had a computer setup in between the front seats...kind of like a police deal.
I was in my Chev Astro at the time and could look down into the 'Stang's cockpit. After a short while he noticed that I was checking the car out and accelerated quickly away from me. Given the way he quickly and so easily out accelerated me, I figured that Ford must of been testing a prototype Mustang with a Chevy V8 under the hood.