Complex sentence: But to do this, they had to specifically change the aircraft such as: moving the wing above the fuselage so six seats could be added; enclosing the cockpit and adding windows and leather padding the interior of the aircraft for the passenger's comfort.
Split into simpler sentences: But to do this, they had to specifically change the aircraft such as moving the wing above the fuselage so six seats could be added. Adding windows and leather padding the interior of the aircraft for the passenger's comfort.