Depending on the model the fleetline series were built from 1947 to 1954.
The Ag. models had some improvements starting with the 1952 models. Example: disk brakes and different decals(red to yellow). There were other changes, but you get the idea.
At the same time the industrials were changed like the Ag. models, and the colors were change from the earlier orange to the yellow. Generally speaking, if a industrial has band brakes it was painted orange. If the tractor has disk brakes it should be painted yellow.