The 05,
06, and 07's utilize the uppfitter switches as you know. The switches have two 30 amp rated (aux1 and 2) and two 10 amp rated (aux 3 and 4). Since this mod requires low amperage to run use 3 or 4. You will have to get to the customer access wires that are located behind the emergency brake you would be looking for the
BCP wire. This wire is
purple with a light green stripe. Take a piece of wire 6 to 8 inches long and connect it to this wire. Next you need to find the orange light blue wire on aux 4 connect this to your BCP wire and your all set to run the high idle feature. This feature will only work with the e brake set and in neutral this does not screw up the cold weather strategy that is preprogrammed. Hope this help.