Hi Jon
Afraid I can't help you with the s/n. But "Airfoil" #4 has a photo of Sugar Train on page 8. Neither the s/n or the code shows... BUT! But the caption states that the code was ZM*S, and the pilot's name is Lt. Earl Miner. By the way, the photo I'm referring to was taken at Fürth, Germany.
I know that's not all the info you were looking for, but I hope this little bit helps.
Sincerely.
Scott