Cool car and worth every dime you are asking. People just do not realize what building a car costs. In FL your car would sell for at least what you are asking.
Stick it on Ebay for a 7 day run just to market it and you will be surprised on the amount of interest you will receive. Also, go to the Boss302 forum and advertise it under cars for sale. A ton of mustang lovers, including racers over at that site.
Just be patient and you will get at least what you are asking. With marketing I think you are undervalued. Good luck.