The front TV appears to be the same set up as in my Sightseer. If so there are several (six?) wood plugs on the frame around the TV. They can be pried out and the screws behind them removed to remove the frame.
Then there are nuts on each side that can be unscrewed from bolts in a steel strap surrounding the TV.The strap is connected to the rectangular steel tubing that forms a frame for the overhead cabinets and is part of the steel frame that surrounds the whole front of the cab.
On mine there is access to the bolts through cutouts in the cabinet walls on each side of the TV.
You can see some of the steel framing in the pictures of my TV change out HERE
. Look for the one tittled "Old TV Removed"