I had a chance to work on the Mustang when I was in the DC Air Guard, at summer camp. The Maryland group had Mustangs and would hold their summer camp at Travis Field in Savannah, GA at the same time as DC. We had 86s. I was an armament technician and we would be at the end of the runway to arm the guns of the airplanes going to the gunnery range. The Mustang had three 50 cal machine guns in each wing, and with the flaps down you could lean over from the back of the wing to charge the guns, which were covered with a panel held on with dzus fasteners. It was neat to stand behind them and lean into the wind as they ran their engines up.