Best way, fly into Salt Lake and rent a car. From the airport you are only 120 miles from the salt flats. if you take your rent a car onto the salt, remember to do a (COMPLETE!) salt removal from every surface of the car, and then wash it again. after it dries, do some donuts in the Wendover dust, and then drive it back to the airport.Trying to do do the Wendover shuttle or Greyhound is disaster waiting to happen... rent the car, and you are there in two hours after your flight arrives.
Jim Keeler