I am currently swapping a service body from a 06' c5500 to a 03' c5500. the service body has a crane and compressor that runs off a PTO. my problem is that the remote that controls the service body also has a start switch to shut off or start up the truck. on the 06' LBZ truck it had a wire tied into pin #21-pink wire at the 58 pin ECM connector. what I have found is that pin is for ignition #1 voltage. what would be the equivalent pin on a 03' LB7 ecm?