Where is Acc wire for Freightliner Cascadia for wiring up dash cam

I can get power and ground from the cb power and ground wires. But where can I get the acc wire so when ever I turn the key the dash cam with turn on instead of having to keep using a cigarette lighter plug?
If you wired yours up feel free to describe how about you got it done. Thx. 2013 freightliner cascadia

 

Can you find a fuse in the fuse box that is powered on with the key?

 

probably can, just have to get a long wire or figure out a good way to route it in.

 

I leave mine running all the time. If I wake up to someone dragging my hood off at a truck stop I want video

 

I would not attempt anything without consulting your trucks electrical diagrams. You risk causing intermittent issues with the circuit in question.