I'm not familiar with your tractor at all but I have one question.
How many lights do you have on your tractor?
Just on the rear or front and rear, usually you will have red turn and flashers on the rear and amber to the front.
Some units will have an amber lens in the front and a red lens to the rear, but many have separate forward and rearward facing light.
They are normally wired in parallel one front and one rear.
Many of your readings seemed to me like you are reading through a bulb.
There is one set of amber, directional/hazard lights on the back. There are also red running lights on a different circuit on the back as well. you can see them in this picture...