The extra $240 is the Ford regional dealer's association marketing fee (FDA).
EVERY Ford dealer has to kick in $240 on EVERY new Ford vehicle they sell for regional marketing programs, regional advertising, promotional events, special regional discounts or option packages, etc. There are NO exceptions.
If you are negotiating off of MSRP you will not see the FDA, it's built into the price. But if you are working up from invoice, the dealer will add in EVERY charge they incur including the $20.49 Ford charges the dealer for the 11 gal of gas that a '05 Mustang comes from the factory with AND the $240 FDA.