Nartsherqatli

Hello, I had spent the last 3 months searching and looking around for a solution with no luck. I own a 2012 chevy silverado that only came with cruise control and no radio steering control. I tried adding the radio steering control with no luck. i wired the swc correctly, and the backlight is on and the resistance changes on the light green wire which is the swc signal when the buttons are pressed. I have a clock spring with the pin C where the light green steering control signal wire should be wired and it shows that the signal is received by the bcm when tested via the obd connection on a "launch" testing device. the rear harness from the radio are shown in the attached images. does anyone know which wire goes from the BCM to the radio wiring harness?