I use mine to keep one of my Streamlight flashlights charged and ready. I occasionally put my battery pack charger for my Milwaukee impact drill on it also. Just gotta remember to hit the button on the dash every few drives to turn it on and keep it charged.
Installed a Molle panel from Builtright Industries. Easy install. No drilling involved. https://builtrightind.com/collections/bedside-rack-systems-truck-bed-molle-panels
My stock 2020 1500 LTZ Z71 is 6' 6" (78") from level ground to the top of the shark fin antenna. I measured it when I first got it for the same reason you mentioned.
I mounted a Streamlight Strion in the bed and use the bed outlet to charge it. I have an Undercover hard tonneau so I have no worries about water getting in.
I had a Havis in my previous gen Silverado and loved it. This time I wanted a more integrated look. It looked great, but I just couldn't see the screens being down so low. Had to modify it to make it work.
Not Ham, but mounted 2 Uniden scanners on a Jottodesk console. I had them mounted inside, but couldn't see the screens due to the angle. I simply installed the faceplates backwards and mounted them externally. I'm happy with my setup.
Ordered my 2020 LTZ 5.3 in January. Got her last month. Best riding truck I've ever driven. Love this color. My 3rd silver Silverado. 5th bowtie truck I've owned.