The EFI Live tune that we did to my 2011 GMC truck took 45 minutes. The computer guru and I spent some time setting the computer up for the different size tires that I was running, the fuel cut off is not so high that it is non-existent, and the tranny shift points are so much more firm it is now a good feeling to drive. He is available any time that I want to do some changes and updates.
GMC Joe, since you are in the NY area you might look in at New Era Performance. They are in your area of the country (Rochester, NY) and they do computer tunes and handle products for our trucks.
http://www.neweraperformanceparts.com/