I would be interested in any reference, RFC marking standard for serial numbers, The location and Rudder fin markings if any.

I am seeing many variations in position, size and additional numbering / colours of the aircraft serial number.

Basically I am looking for the serial number standard Sept,Oct 1918 for the E XXXX serials.

On a S.E 5a, may be of 56 Sqd.

I am trying to tie down on the {rear fuselage serial in white E XXXX, on olive}, with a Black XX on the white bar of the tail fin.

The last two numerals, of the serial number, can be the two numbers on the white vertical bar of the Tail fin.