Thanks Deejay and Tezza.
I understand Deejay that the codeing by Scott Bonnar is not accurate, but i at least want to try to estimate approx year that mowers were made. The more info i can get, the better i can try to estimate this. I have got some info of certain chasis numbers where changes to parts were made, so i want to match this to mowers of known purchase dates that may or may not have these changes. Again it will only ever be an estimate, but better then nothing.