Were they stolen or did you give them to them as payment for "Stripping" it out for a fiberglass /stage 2 setup, which was obviously never completed.. It's really sad to see that car like that, but having known what was going on, I think you should have taken it home while it was stll in the other shop. I seen it there for the longest time and it was all in one peice.
Didn't you come down before the car went to that shop and see what was going on, did nothing seem odd to you? I'm not trying to sound mean but at that time, it was pretty much kissing your car goodbye and you knew it.
Now that car is still in good shape, nothing has been maimed, but it would need seats, hood, engine, rear end, and wheels.
You could probably get it rebuilt for less than the cost of a new gn, Unless you're just trying to get rid of it and get a new gn anyhow.