I have no idea of the floorplan of your MH, but in my MH there is no access panel for the shower valve. In mine you remove a wall panel in the bedroom to access the shower controls - it's not that big of a deal. Your MH could be similar.
I had pulled the paneling to see where the support was for a bedroom TV. My MH didn't come with a TV there, but it was an option. The support was there, even though it didn't come with a TV. It seemed like it would be nice to have a 2nd TV, but we never seem to use it.