Bad, bad day.. (head gasket)

You probably already posted this, but is your check engine light on? Did you read the codes? Man, I think this guy is B/Sing you BIG TIME! All of those things are wrong with your car?? I seriously doubt it. It's a shame your Dad doesn't trust you to work on your own car. He might shell out all this money and you could still have problems with your Mustang. The mechanic might want to keep you coming back. Many of the things this guy stated were wrong with your car...are popular things that any mechanic could (& will) lie about. You should have him prove that those things are bad. Have him show you. Check the TPS yourself, and the radiator being incorrectly mounted?? I'm sure that can be easily fixed...it's just a radiator man. And what's he going to do with the #8 cylinder to bring it back to life? New rings...a valve?? You need to make sure you (& your Dad) aren't getting taken to the cleaners here. Personally, I'd take it somewhere else...& get a 2nd opinion....