Doing as you describe is a good display option but was almost never done in real life (IRL) when the engine was being serviced, both panels were open. same with the gun ports. I would have one side open, and the other closed, so you could see both options. If I were building a diorama depicting the aircraft being serviced, then all panels would be open.
One side closed up, ie, engine and guns on right, open, and left closed, or vice versa, looks good from both sides. like the submarine kits open on one side to show the interior, and hulled on the other side.