When sitting in a WWII fighter, is it normal that the natural position does not line you up with the site and you have to hunch over or duck to get on it? Not being a smart pants, I really have no idea.
First, keep in mind that pilots were not all 5ft 8in. Meaning, they were not all the same height which in turns makes a pilot having a natural line of sight through the gun sight, if it is mounted centrally above the instrument panel, a rare event. Secondly, many aircraft had the sight situated off to the right slightly so it would not cover up important gauges. So, take those two variables and it is easy to see that having a natural line of sight through the gun sight was actually pretty rare. With that said, I'm sure there was some adjustment to put the projection of the gun sight were the pilot wanted and that may have been enough for some pilots who flew the planes with the centrally mounted sights.
The easiest way to show you the issue at hand is this: hop in to the Mossi FB Mk IV, that is the model with the guns. Hit the "Home" key to put you in the default view in case you've manually moved your sight position. HTC set that as the "default" view since it has guns. Now hop in to the Mossi B Mk XVI and hit the "Home" key and notice the position vs the first Mossi. Quite different, eh? The view is exactly the same from the pilot's chair since they are the same plane but serve different roles, but in the FB Mk IV HTC defaults the view to the gun sight. I think the default view should be the same in both planes: centered over the pilot's chair.