If the cts is for an edge juice it cannot be used for your efi live switch it must be a cts insight monitor. Also I had someone wanting me to do the same thing with their truck when i was installing efi live on it and the monitor wouldn't work unless it was hooked up to the edge juice. It had to be hooked up to the obd2 plug along with the edge juice. Best bet would be to sell it and buy a cts insight.
I did EFI on an LLY yesterday that had an edge juice with a CS monitor. After unplugging the Juice box and its piggy back harnesses the monitor would power up via OBD2 but would not function. Screen merely indicated it could not communicate with the juice. We ended up just installing a CTS monitor and Steve changed the tune for electronic tune switching within the calibration.