Has anyone found a way to change the default screen on this unit? I have it installed in a motorhome and would like to have the default screen be the rear-view camera as it is nice to be able to check on towed units behind us with just a glance. However the way the system is set up from the factory anytime you do anything else you have to work your way through the menu's again to reset that view. Not the safest way to manuever down the highway, looking at your touch screen rather than the road.