Been searching high and low and being new to this, the credit system it's a little confusing, but I'm a fast learner. 2015 Silverado 5.3 with 6L80 trans. Just rebuilt the transmission w/new converter and just about to finish installing a DOD delete cam, lifters, etc. Need to turn DOD off and change some transmission settings. Does this require 2 credits to turn off the DOD and 2 more credits to reprogram the transmission? Also in my search I thought I saw something about credits being tied to the vehicle which I understand, but are they permanently tied to the laptop you use to tune with or can you use different laptops on the same vehicle with your already used credits? Thank You.