On the original 108-2 models that came off the factory line in May of 1947, the registration numbers, or ‘N’ numbers, were 3″ letters on the vertical stab of the aircraft and in 12″ numbers under the left wing.  The original ‘N’ number was NC9391K, ‘C’ for standard.  That designation was dropped by the FAA in the late 40’s, so it was removed from the aircraft some time later and became just N9391K.  Someone also added 12″ registration numbers to the side of the fuselage at one point.  The original aircraft did not have those.

The photo below shows a 108-2, serial number 2382, from the factory.  This Stinson is just 9 numbers away from Grandpa’s (2391) and was delivered on April 18, 1947.  Grandpa’s was delivered on April 11, 1947.  Strange Grandpa’s was delivered earlier.  This Stinson has the original NC registration number on the tail and none on the side of the fuselage.  

At this point I want to take it back to the original off the factory floor scheme, so I plan to have it look just like the one above.