Well, Winnebago routinely changes the radio/gps/infotainment systems in their motorhomes. So, we don't know all that much about what your rig has right now. Plus, there are no guides or common upgrade devices that "everyone" uses or recommends. I'd guess the common response would be "Huh?"
What we tell people is to go to an Audio Sound shop and talk to them show them a photo of what you have or better yet take your Minnie Winnie to the shop. Many people simple call Crutchfield and talk to them about what's available.
Neither Winnebago, nor any Winnebago dealer is going to offer any advice on this. It's you and the entire Car Audio marketplace to investigate.