To quote the rule book verbatim dated 2012 (not the latest) under Classic Ploughing (a) Mounted ploughs in production before 31st December 1976, but excluding Fiskars, Kverneland Hydrien and Super Hydrien and Ransomes/Bonning, YCN,UCN and SCN bodies are not allowed.1976 or per Q cab is the cut off date for the tractors,
as for the ploughs see post 12,
I am not saying I agree with it, but think that is the reason for it
(b) Plough bodies to be in production before 31st. December 1976.
If these excluded bodies do not fall outside the date rule they are specifically excluded for a reason. What reason?