Second part first, yes, the gun was mounted on the upper wing to fire over the propeller arch. This was to get around the problem of firing through the prop, as at the time there was no workable synchronized gear for shooting through the prop. There were several different type mountings for the top wing Lewis gun. The guns were fired by means of a cable system. The best one was the Foster mount that allowed the pilot to reach up and pull the gun back down a railing so he could reach the ammo drum, for reloading or to aim the gun up, in the case of his making an attack on an aircraft from directly underneath. The gun could then be slid back up the railing, assisted by a bungee cord. Other mountings were fixed and did not allow for reloading, at least not easily. All over wing mountings were fixed to aim straight ahead and were aimed by pointing the aircraft at the target. As things became more sophisticated, sights were incorporated so the pilot didn't have to "spray and pray". The Nieuport JJD has modeled has a scope type sight that follows the line of the gun barrel, just as a scoped rifle would, only it is on the pilots level instead of on the gun itself. The overwing mountings became obsolete with the advent of synchronized machine guns but remained in use, most notably on the SE-5. This was due to the British affection for the overwing mount (mostly Albert Ball's influence). -- Al