Gary, I just removed my unit (like yours) last week but only after installing the new antenna and using it a year to be sure everything was what I wanted and needed.
In my case, I found a waterproof box with lid, and routed the RG-6 video cable and the 10 to 12 conductor control cable (that runs to your existing Datron controller) into that box mainly for future use. You have a bunch of wires that are usable for anything you might want to use them for in future years.
Again, in my case I added a RG-6 in-line coax connector and added another RG-6 cable in the new box on the roof and that routes to the rear bedroom via the roof.
This setup gives you many possibilities for functionality in the future for the audio/video system between the front and the back of the coach. Of course, if you do everything wireless then this is academic.
I would never just cut your old cables off and seal up that hole for these reasons.
Larry Fritz