You should look for the normal things like making sure there is no oil in the water and no water in the oil.
Start it and drive it some to see if the alternator is charging, what temp the engine gets up to and how it handles.
After you turn the engine off watch the air pressure, it should not drop noticably. I am pretty sure it has air brakes.
You should not need a CDL since it is for personal farm use.
I registered my '77 GMC 6500 as a farm vehicle and got insurance from Progressive Commercial because my auto insurance company only insures up to 1 ton vehicles.
Danny
