Driving the car to 6,000 rpm is not mis use, that's what the car was built for. I can easily see how the previous owner knew something was wrong and ditched the car before it went. Dealerships shouldn't take cars like this in without having it checked out and I'm 99.9% sure the dealership knew something was wrong because that's a lot of car for 29 grand. OP you can probably part that thing out and make a lot of your money back. It's really not the OP's fault that it broke even if he got on it, that's what the car was built for. Who buys a Shelby GT500 and shifts at 2500 rpm? OP you should try and find a used short block and fix anything else that's wrong with it, even if you have to use a credit card and then go after the dealership. Really a crappy situation