I'm very new to this and cant seem to find the info I need to load the tunes from Twisted Diesel Tuning on the autocal to my truck. Its an 03 LB7 Duramax. Do I need to license the unit before I do anything else with it? I assumed that this was gonna be a plug and play kinda thing, but it seems way more complicated then that, or am I missing something? Are there any easy step by step instructions somewhere that I can follow?