Per email from Ford below:
Congratulations on your 2015 Mustang
vehicle order and we appreciate your continued loyalty to the Ford family. We are happy to document your feedback and would like to announce that the 2015 Build and Price application is expected to launch by the end of this month (June) and you will be able to see all the features, such as the 68B Interior Color option. Once you complete your build, we recommend printing your Summary page to use as a reference when you place or modify your order with your dealership.