Where Do You Check The Transmission Fluid Level On A 2005 Ford Mustang With A Automatic Transmission?

There is no dipstick, but a level tube is built into the centre of the drain plug (hex key).
Run car up to 'normal' temperature, raise the car on a level lift, remove centre hex plug.
Fluid should occasionally drip from hex plug hole. No drips fluid too low, pours out fluid too high.

The fluid is Mercon V, do not use anything else !! I.e Dexron etc!