I see there are a load of places here in the UK who can 'correct' my car's mileage... it's of no interest to me (it's already higher than average anyway as per the service file) but got me wondering if it could have already been done to the car? Are there any ways of checking? On my 997 it wasn't easy to do as the milage was recorded by a few modules, also you could check the engine run time, average speed and see if they concur... what abut on the GT though?