Adding auxiliary work lights to Cascadia

My 2020 Cascadia does not have work lights on the back of the cab and I'd like to change that. I'm not trying to cut holes in the cab and give it a factory look. Just want to throw a couple flood lights on the inside of the fairings.

I've got 3 optional switches on my dash (Opt 1, Opt 2 and Opt 3). It's my understanding that these switches lead to some wires on the frame that I can tap into. Has anyone done this that can share some details? Location of wires and whether an inline fuse is needed?