I have been looking at different dealers websites for pictures of the Universal Docking Station (UDC) for the Elk Ridge and I cannot tell from the pictures if your unit will have provisions for a roof top mounted dish or not. I have a 2009 Big Country 3490RB and it has, in the UDC, two sets of Sat inputs. Sat 1 and Sat 2 and Roof 1 and Roof 2. When installing a roof mounted dish on my 5th wheel, I would have to jumper the roof input to the sat inout and it would be good to go. So with that being said, make sure you talk with your dealer about that option. My unit has the roof wiring installed and in the ceiling in the bedroom. They call them preinstalled roof coils for the sat wiring.
Good luck with your new Elk Ridge. I looked hard at them before deciding on the Big Country.