If your car is any kind of an investment in 20 years I will PayPal you 1,000 bucks. A GT500 might be, but a run of the mill mustang they sell 100,000 a year of, no chance.
OP I know you love your car but they are a "dime a dozen" vehicle. I love my GT but I DD in all weather (yes, winter) and in a few years my 14 will be valued darn close to your 14, which will be a lot less than what we both paid for it. My suggestion, have the dealership fix it (repaint or whatever) and put it behind you. Mustangs are to be driven. A Boss 302 may be worth something in a couple of decades but not the run of the mill GT. Take it to your local drag/road course and have fun with it. After a few thousand miles you will forget all about this incident.