How do I reflash my ECU without going to Ford?

I bought my 13 GT500 with some performance parts and an unknown tune. I've since taken it to a local performance shop and had a custom Dyno tune put onto the car. After I use my SCT X4 to take my custom tune off and revert it back to this "unknown" tune. How do I reflash it to the factory settings? I'd like to avoid taking it to Ford to avoid a high cost. I've already called several dealerships and they want at least $250. I love in the Dallas Ft. Worth area.

SCT might be able to give you a stock tune. Also I was a Ford Tech many years ago and we only charged 1 hour labor to flash to the latest factory tune. If you can make small talk with one of the techs at the dealership you can often find one who will do it on the side.