I don't know a lot about the s197 body styles, but don't they have a hydraulic clutch? Do you think it's possible maybe it just needs to be bled a bit?
Honestly though, like some other people have said, I have given up letting anyone else touch my car. I've done all the work on the Mustang myself for pretty much for the life of the car, minus when I first bought it, just because I can afford to have it down for a week or two at a time, but with my DD, I would sometimes drop it off at the shop so I could still make it to work that day, then just pick it up when my shift ends. I've consistently been screwed, either with prices or shotty workmanship, though. After doing the math, it's honestly more cost effective for me to just take the day off and do the work myself. Plus then I know the fix is permanent.
With that said, a clutch change isn't that big of a deal. If you can make it back home, I would grab a knowledgeable friend and change it out if I were you.
What does your dyno sheet trap?