My 2000 CSVT is also a test vehicle. I know the history, though. My friend works for Ford. He is friends with a guy who is an SVT design engineer. My CSVT was the engineer's personal vehicle to drive around and "test". For instance, apparently there were some test instruments attached to the section where the theft deterent light is at some point. Well, after some period, Ford was putting the car up for sale (with 14,000 miles). This engineer was going to buy it for himself, but knew my friend was looking for a car like it and let him buy it. After about a year and a half my friend got the itch for a new Mustang GT and sold me his CSVT.
Now, whether the cars being test vehicles is good or bad I don't know. I think you could argue either way. The way I chose to think about it was that I know for certain that for the first part of its life, my car had all the required service done and was maintained very well.
I find it very interesting that someone has come across that same TEST VEHI as my car has. Let me know if find anything out. Also, if you give me some more of the vehicle info, I may be able to find something more out for you through my friend. E-mail me if you want at
kazooben@yahoo.com.