Serial numbers

[Billy 1931 Model A]

Perhaps you can help me: I think my car is a 1931 roadster 40B. It has cowl lights and a rear mounted spare. But the serial number stamped on the engine is A2650230, which would indicate the engine was manufactured in November 1929. The serial number stamped on the frame is not visible. However it must be 1007955, because a few years ago, prior to my ownership, someone riveted a little plaque on the firewall with S/N 1007955. 1007955 would indicate a date of manufacture of February 1929. Can you make sense of these serial numbers?