Just get an auto cal from a good tuner. There are only a handful of tuners in the U.S that i would trust enough to buy tunes from. I'm not going to list names, do your own research. There's enough info here @DD about tuners to choke a horse so dig in, read until your eyes are dry and bloodshot, then take your best guess....
Only a damn fool would buy software off ebay, when you can so easily procure the products from the original source, unless of course it is the tuner, the software is new etc.
Even then i would be sceptical.
If you get an auto cal any changes can be made to the tuning through an email to and from your tuner, once you download the efi live format from efi live, you can take live data from your truck with the auto cal download it to the efi live program and then email the log to your tuner, they interpret the info and tailor the tune to your truck.