Like 74gtstang and Katastrophe mentioned, when in SelectShift mode, the gears will show next to your odometer, guys. I hope this helps.
Your "answer" is only partially correct. If you change to "Sport Mode," on the auto transmission, and ht the OK button on the steering wheel, the "current gear" will not show on the dashboard display. It will only be displayed if you first make a manual shift with the "shift button" on the side of the gearshift handle. If you allow the transmission to continue in "automatic mode - even if on Sport setting-," the current gear is not displayed.
2013 Mustang GT Premium Convertible
Candy Apple Red, Auto, FRPP Tune, GT500 Axlebacks, KONI Yellow Sport (adjustable dampers), FRPP Front and Rear swaybars, Custom Removable 4 Point Roll-Bar, BOSS 302 Low Expansion Brake Lines, Roush side splitters, GT500 spoiler, Redline Tuning hood struts,18" Ford Chromed Aluminum Wheels (9R3Z-1K007-A), Michelin Pilot Super Sports - 235X50X18
2011 Mustang V6 Premium Convertible - Gone