IMHO these early planes were low tech. The gun sights often were ornaments. A pilot uses the whole plane as his gun and because of knowing his weapon in effect he could fire from the hip rather than take a long slow look down the barrel and have all day to press the trigger at a tin can sitting on a fence post. If you are fixated on your gun sights you are likely to get shot down. From behind I center the enemy plane in my relation to the forward view from the cockpit and then it is a matter of proper elevation angle. I use the tracers at all times time fine tune my aim. Now deflection shooting is more of an art as you are in fact aiming your shots for where you hope the enemy will be rather than where he is. You "lead" or fire in front of the enemy plane. How much lead you use depends on factors like the speed of the e/a, your speed, distance and angle of attack. So relying on a gun sight is a bad form of attack as I see and will get you dead pronto. Become one with your plane ,young skywalker, and in time you will not think about aiming but will know when the time is right.