I know of an 806 gas that was weighing 5500 empty, pulling 6000. Of course the gas engine is lighter than the diesel, and he had a custom lightened schwartz type front end, only 2 gears, had the reverse and low gears machined light so they were only for loading, and a whole bunch of the obvious!
You can remove the trumpet housings then take a large hole saw to the cast. Lots of weight to loose there. As mentioned Hydraulics,3pt, pto, weld on hubs, cast grill housing,
