I have a B in my shed that has the 2 fuel tanks for starting of gas and switching to what we now think of as diesel now. At least that is what I understand about it.
Hasn't run for a few years now but I just used gas only when I had it running.
I think it is a '39 model.

My father had a B that had a loader on it not sure the year of it maybe mid 40ies.
All of those were on rubber.

The loader was used on our farm and my 2 uncles but I remember them forking the manure pile on ground driven spreaders to haul to field.
The 3 brothers had 2 spreaders so the owner of the manure pile forked every load while the visiting brother got to load his spreader and has to field.
The loader changed that manual chore.

BTW spreaders were horse drawn when they were forking by hand.