Series IIa ageing

I have a series IIa. The plate in front of the gear lever says The Rover Co Ltd Birmingham England Car No 141102158. Can anyone tell me what age the vehicle is? I have owned it since 1983. It was military before civilian, its civil plate ends in J but I am sure it is not its year of manufacture. I keep being asked its age maybe someone out there can give me the answer?

if i'm correct that chassis number is for a 1960 series 2,see the pm i sent you for more info.

yup, you are right big chasp, mine is a 1960 s2 and it starts 141, i seem to remember something about the first 5 digits reffering to the year and model