On our 2021 Mallard M260 we carefully removed the cable TV outlet/amplifier and used a flashlight, mirror, and tape measure to locate the backing plywood. After that it was easy to screw the TV mount to the backing plywood. We used this: PERLESMITH UL Listed Lockable RV TV Mount for Most 13-42 Inch TVs, RV TV Wall Mount for Camper Trailer Motorhome Boat Truck for a 32-inch flat panel Roku TV. We used the pre-installed Winegard AIR 360+ V2 antenna. We added a WiFi Ranger Osprey Category 12 with an AT&T 100 GB $55/month data plan. Both the Winegard and Osprey have served us well in our travels.
We really like it. We are retired and it was the right size for us. Light enough for our truck big enough to be comfortable in. We bought it new September 2021 and put 14,000 miles on it in a year. We stayed warm in it at 14 degrees and cool in it at 109. Traveled 5 months straight looking for a new place to call home. Only had two issues both repaired under warrantee. Small tear in the flooring from a screw that was too long and the vent pipe for the shower that came loose. We have not done any modifications. We would like to replace the sofa with recliners but have not found ones we like and that are light weight. Safe travels and enjoy the camping life.