Looking where to tap in to the CHMSL brake light in the cab for sander brake light on my '22 f-350.... found a labelled wire cluster near the foot well fuse panel and one marked CBL30 Yellow with blue stripe.... Same color as the CHMSL tap at rear of the truck. Used a test light and it has power with the brake pedal pressed.....there's also CBL22 didn't test it. Anyone know if this is the correct power source to tap into?? or is it connected to something else?
Thanks
Rygar.

 

You may find some helpful information in this thread.

https://www.ford-trucks.com/forums/1...bed-light.html