I have just acquired a '43 Royal Enfield WD/CO, and so now have to start some research.
The bike looks like it has been given a sort of renovation, but was never really finished. Some bolts are loose, the speedo is missing, some threads are damaged or have wrong bolts put in.
I don't know when this was done; however, I have no intention of trying to make this a restoration project. The bike will be perfectly rideable, and in any case, I am sure that once the Army got hold of these bikes they didn't stay standard for long.
So all I will do is make it mechanically OK, and ride it.
Frame is 15654, engine 10933 - if anyone has any history, I would be glad to hear from them.