I had a 1938 Z almost identical to this one when I was a kid .. I don't recall the Fenders like that … It had the same spoke wheels.. I was told it came on steel and some one cut the steel wheels off and welded the rims for pneumatic tires in place .. Mine had the flywheel on it as my Grandfather used it to pump water through a rather large water pump .. I was not sure if mine was a 1936 .. not sure what year was the first year for them Mine had a gas tank only had no idea why there would be two tanks .. John Deere's started on gas and ran on tractor a gas a very low octane gasoline .. that was a little more like Kerosene .. It seems my brake pedals were more flimsy and had catches to lock them in park .. as you would need to run a belt .. You did not mention the slide shifter which people either loved or hated .. I liked the way it worked.. My Neighbor also had a tractor like this before I was around and it was the only tractor he ever owned that his wife was willing to drive .. They got marred when they were both married and she never got a drivers license.. She was W.E. Upjohns Personal secretary in her younger years and she lived in downtown Kalamazoo before she met the Farmer that she marred when she was 40 years old ..
I can't remember if '36 or '38 was the first year for this tractor .. but before this it would have been like a JT and it was a dark color and was a Twin City I think .. seems it was a 231 cube side valve motor ..