Wiring for cap lights and lock on a 2019 Big Horn

[KJC12]

I recently picked up the cap in the picture for my 2019 1500 Big Horn. The guy I bought it from claimed he had it on his Big Horn and had it connected it to wiring behind the bed for the brake light, dome light and lock/unlock feature with the key fob.

Can anyone confirm if this is doable with wiring that should already be in place? And if so, how do I get to that wiring?

 

[KJC12]

Bump

 

[Richard320]

I think these links will help. I haven't done it, so don't ask me any more. 2021 Laramie 3rd brake light wiring