Ok after almost a month trying to figure this bull out finally got it, 07.5 with G56 you need to have the idle up/ Pto enabled by your dealer, then under your dash on the C2 connector (The connector that goes through the firewall) There should be a Dark green and orange wire. Ground out this wire and enjoy. On some of the trucks (Earlier 6.7's) there is a six pin connector that looks like your brake bake pedal switch with only two wires inserted in it, one dark green w/ orange stripe and one black one. Connect the dark green and the black one to ground it. (The black one is ground). Engage your parking brake hit cruise and set, then adjust the idle with the right cruise switch, accelerate to increase to 1500 max and decelerate to decrease. Note your dealer will try to sell you a switch they call a clutch travel switch (the exact same switch as your brake pedal switch) I see no need for this. Enjoy