The programming should take 30 minutes tops, and that's even on the high end. The actual unit replacement, allow two hours. Anything else they told you was BS. It took three radios and me finding the afore mentioned TSB before my dealership was miraculously able to get the last radio working (although me telling them the TSB # had nothing to do with the fact my radio suddenly lit up and worked 20 minutes later). Like the others have said some of the dealers are very, very, very uninformed when it comes to the issues the Mustangs can have.