Thanks, and that is why I questioned it in my first post. Found a work-around utilizing a null modem cable and use the rear port for the remote head. I understand that firmware updates must utilize the front port, but until there is an update and/or money presents itself I will deal with that when it happens.
There was an eBay seller that sold a mating connector on a cable about a foot long. I don't recall what the connector is called but the cables the guy sold had the Uniden style plug on one end and an A male USB on the other. So it seems the connector was really intended for USB in its original design.
I bought a bunch of them from the eBay guy for like a buck each and just cut off the USB ends and wired them to 1/8th inch stereo jacks or DB9's so I could use the remote heads from the front port if needed.
Later, I added a stereo jack on the rear of all my 996 models as I hate cables sticking out the front. I left the front port wired so I could use it if the radio was mounted. Of course you could not use the new rear port and the front port at the same time.
I did the same with my GRE models and their front PC/IF jacks.
I wish Uniden would have duplicated the front USB jack onto the rear chassis for the 536HP models. Then you could just leave a short USB extension plugged into the rear jack for programming changes and updates. That would also be easy to do but not worth voiding the 3 year warranty as who knows what other problems may surface with the new x36HP models.
I use the rear GPS port for logging and monitoring but you can't use it for programming. That at least keeps the front cable out of the way until I need it.