Adding Bunk windows to cascadia

How are y’all… I was wanting to add bottom bunk windows to my 2020 Freightliner as it did not come with any windows. I have seen some people cut out windows and install them. I have only seen one video on YT of cutting out the side and putting in the window but not to much information. I can order the windows for under $200 bucks, but I am curious to what else I might need as far as interior parts go and if it can be done. I assume I need the interior window trim to start (part # ?) and the windows. Any insight would be nice . Thanks

 

Before going tearing the truck apart , I am wondering if I have to get that back bracket separately. I am guessing that bracket allows the trim to be bolted to it